{"id":21133,"date":"2021-12-17T16:19:19","date_gmt":"2021-12-17T09:19:19","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=21133"},"modified":"2021-12-17T16:19:21","modified_gmt":"2021-12-17T09:19:21","slug":"hoan-vi-chinh-hop-to-hop","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/hoan-vi-chinh-hop-to-hop\/","title":{"rendered":"HO\u00c1N V\u1eca, CH\u1ec8NH H\u1ee2P, T\u1ed4 H\u1ee2P"},"content":{"rendered":"\n<p><\/p>\n\n\n<h2><strong>A \u2013 L\u00dd THUY\u1ebeT T\u00d3M T\u1eaeT<\/strong><\/h2>\n<p><strong>I. Ho\u00e1n v\u1ecb<\/strong><\/p>\n<p><strong>1. Giai th\u1eeba:<\/strong><\/p>\n<p><img decoding=\"async\" width=\"119\" height=\"24\" class=\"wp-image-21134\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_256-19.png\" alt=\"IMG_256\" \/> Qui \u01b0\u1edbc: <img decoding=\"async\" width=\"47\" height=\"24\" class=\"wp-image-21135\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_257-18.png\" alt=\"IMG_257\" \/><\/p>\n<p><img decoding=\"async\" width=\"111\" height=\"33\" class=\"wp-image-21136\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_258-19.png\" alt=\"IMG_258\" \/><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"198\" height=\"55\" class=\"wp-image-21137\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_259-17.png\" alt=\"IMG_259\" \/> (v\u1edbi <img loading=\"lazy\" decoding=\"async\" width=\"50\" height=\"22\" class=\"wp-image-21138\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_260-19.png\" alt=\"IMG_260\" \/> )<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"294\" height=\"55\" class=\"wp-image-21139\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_261-16.png\" alt=\"IMG_261\" \/> (v\u1edbi <img loading=\"lazy\" decoding=\"async\" width=\"50\" height=\"22\" class=\"wp-image-21140\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_262-17.png\" alt=\"IMG_262\" \/> )<\/p>\n<p><strong>2. Ho\u00e1n v\u1ecb (kh\u00f4ng l\u1eb7p):<\/strong><\/p>\n<p>M\u1ed9t t\u1eadp h\u1ee3p g\u1ed3m n ph\u1ea7n t\u1eed (n \u00b3 1). M\u1ed7i c\u00e1ch s\u1eafp x\u1ebfp n ph\u1ea7n t\u1eed n\u00e0y theo m\u1ed9t th\u1ee9 t\u1ef1 n\u00e0o \u0111\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t ho\u00e1n v\u1ecb c\u1ee7a n ph\u1ea7n t\u1eed.<\/p>\n<p>S\u1ed1 c\u00e1c ho\u00e1n v\u1ecb c\u1ee7a n ph\u1ea7n t\u1eed l\u00e0: <img loading=\"lazy\" decoding=\"async\" width=\"67\" height=\"27\" class=\"wp-image-21141\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_263-18.png\" alt=\"IMG_263\" \/><\/p>\n<p><strong>3. Ho\u00e1n v\u1ecb l\u1eb7p:<\/strong><\/p>\n<p>Cho k ph\u1ea7n t\u1eed kh\u00e1c nhau: <img loading=\"lazy\" decoding=\"async\" width=\"112\" height=\"27\" class=\"wp-image-21142\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_264-17.png\" alt=\"IMG_264\" \/> M\u1ed9t c\u00e1ch s\u1eafp x\u1ebfp <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"17\" class=\"wp-image-21143\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_265-17.png\" alt=\"IMG_265\" \/> ph\u1ea7n t\u1eed trong \u0111\u00f3 g\u1ed3m <img loading=\"lazy\" decoding=\"async\" width=\"20\" height=\"30\" class=\"wp-image-21144\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_266-17.png\" alt=\"IMG_266\" \/> ph\u1ea7n t\u1eed <img loading=\"lazy\" decoding=\"async\" width=\"49\" height=\"30\" class=\"wp-image-21145\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_267-18.png\" alt=\"IMG_267\" \/> ph\u1ea7n t\u1eed <img loading=\"lazy\" decoding=\"async\" width=\"75\" height=\"27\" class=\"wp-image-21146\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_268-18.png\" alt=\"IMG_268\" \/> ph\u1ea7n t\u1eed <img loading=\"lazy\" decoding=\"async\" width=\"22\" height=\"27\" class=\"wp-image-21147\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_269-18.png\" alt=\"IMG_269\" \/> <img loading=\"lazy\" decoding=\"async\" width=\"192\" height=\"31\" class=\"wp-image-21148\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_270-16.png\" alt=\"IMG_270\" \/> theo m\u1ed9t th\u1ee9 t\u1ef1 n\u00e0o \u0111\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t ho\u00e1n v\u1ecb l\u1eb7p c\u1ea5p <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"17\" class=\"wp-image-21149\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_271-18.png\" alt=\"IMG_271\" \/> v\u00e0 ki\u1ec3u <img loading=\"lazy\" decoding=\"async\" width=\"122\" height=\"31\" class=\"wp-image-21150\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_272-18.png\" alt=\"IMG_272\" \/> c\u1ee7a <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"22\" class=\"wp-image-21151\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_273-16.png\" alt=\"IMG_273\" \/> ph\u1ea7n t\u1eed.<\/p>\n<p>S\u1ed1 c\u00e1c ho\u00e1n v\u1ecb l\u1eb7p c\u1ea5p <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"17\" class=\"wp-image-21152\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_274-18.png\" alt=\"IMG_274\" \/> ki\u1ec3u <img loading=\"lazy\" decoding=\"async\" width=\"122\" height=\"31\" class=\"wp-image-21153\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_275-17.png\" alt=\"IMG_275\" \/> c\u1ee7a <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"22\" class=\"wp-image-21154\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_276-18.png\" alt=\"IMG_276\" \/> ph\u1ea7n t\u1eed l\u00e0:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"270\" height=\"57\" class=\"wp-image-21155\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_277-18.png\" alt=\"IMG_277\" \/><\/p>\n<p><strong>4. Ho\u00e1n v\u1ecb v\u00f2ng quanh:<\/strong><\/p>\n<p>Cho t\u1eadp A g\u1ed3m n ph\u1ea7n t\u1eed. M\u1ed9t c\u00e1ch s\u1eafp x\u1ebfp n ph\u1ea7n t\u1eed c\u1ee7a t\u1eadp A th\u00e0nh m\u1ed9t d\u00e3y k\u00edn \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t ho\u00e1n v\u1ecb v\u00f2ng quanh c\u1ee7a n ph\u1ea7n t\u1eed.<\/p>\n<p>S\u1ed1 c\u00e1c ho\u00e1n v\u1ecb v\u00f2ng quanh c\u1ee7a n ph\u1ea7n t\u1eed l\u00e0: <img loading=\"lazy\" decoding=\"async\" width=\"123\" height=\"31\" class=\"wp-image-21156\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_278-18.png\" alt=\"IMG_278\" \/><\/p>\n<p>\u00a0<\/p>\n<p><strong>II. Ch\u1ec9nh h\u1ee3p<\/strong><\/p>\n<p>\u00a0<\/p>\n<p><strong>1. Ch\u1ec9nh h\u1ee3p (kh\u00f4ng l\u1eb7p):<\/strong><\/p>\n<p>Cho t\u1eadp h\u1ee3p A g\u1ed3m n ph\u1ea7n t\u1eed. M\u1ed7i c\u00e1ch s\u1eafp x\u1ebfp k ph\u1ea7n t\u1eed c\u1ee7a A (1 \u00a3 k \u00a3 n) theo m\u1ed9t th\u1ee9 t\u1ef1 n\u00e0o \u0111\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t ch\u1ec9nh h\u1ee3p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed c\u1ee7a t\u1eadp A.<\/p>\n<p>S\u1ed1 ch\u1ec9nh h\u1ee3p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"332\" height=\"55\" class=\"wp-image-21157\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_279-16.png\" alt=\"IMG_279\" srcset=\"https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_279-16.png 332w, https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_279-16-300x50.png 300w\" sizes=\"(max-width: 332px) 100vw, 332px\" \/><\/p>\n<p>\u00b7 C\u00f4ng th\u1ee9c tr\u00ean c\u0169ng \u0111\u00fang cho tr\u01b0\u1eddng h\u1ee3p k = 0 ho\u1eb7c k = n.<\/p>\n<p>\u00b7 Khi k = n th\u00ec <img loading=\"lazy\" decoding=\"async\" width=\"121\" height=\"32\" class=\"wp-image-21158\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_280-18.png\" alt=\"IMG_280\" \/><\/p>\n<p><strong>2. Ch\u1ec9nh h\u1ee3p l\u1eb7p:<\/strong><\/p>\n<p>Cho t\u1eadp A g\u1ed3m n ph\u1ea7n t\u1eed. M\u1ed9t d\u00e3y g\u1ed3m k ph\u1ea7n t\u1eed c\u1ee7a A, trong \u0111\u00f3 m\u1ed7i ph\u1ea7n t\u1eed c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c l\u1eb7p l\u1ea1i nhi\u1ec1u l\u1ea7n, \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp theo m\u1ed9t th\u1ee9 t\u1ef1 nh\u1ea5t \u0111\u1ecbnh \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t ch\u1ec9nh h\u1ee3p l\u1eb7p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed c\u1ee7a t\u1eadp A.<\/p>\n<p>S\u1ed1 ch\u1ec9nh h\u1ee3p l\u1eb7p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed: <img loading=\"lazy\" decoding=\"async\" width=\"66\" height=\"35\" class=\"wp-image-21159\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_281-17.png\" alt=\"IMG_281\" \/><\/p>\n<p><strong>III. T\u1ed5 h\u1ee3p<\/strong><\/p>\n<p>\u00a0<\/p>\n<p><strong>1. T\u1ed5 h\u1ee3p (kh\u00f4ng l\u1eb7p):<\/strong><\/p>\n<p>Cho t\u1eadp A g\u1ed3m n ph\u1ea7n t\u1eed. M\u1ed7i t\u1eadp con g\u1ed3m k (1 \u00a3 k \u00a3 n) ph\u1ea7n t\u1eed c\u1ee7a A \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t t\u1ed5 h\u1ee3p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed.<\/p>\n<p>S\u1ed1 c\u00e1c t\u1ed5 h\u1ee3p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed: <img loading=\"lazy\" decoding=\"async\" width=\"174\" height=\"59\" class=\"wp-image-21160\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_282-18.png\" alt=\"IMG_282\" \/><\/p>\n<p>\u00b7 Qui \u01b0\u1edbc: <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"32\" class=\"wp-image-21161\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_283-17.png\" alt=\"IMG_283\" \/> = 1<\/p>\n<p>T\u00ednh ch\u1ea5t:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"570\" height=\"53\" class=\"wp-image-21162\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_284-17.png\" alt=\"IMG_284\" srcset=\"https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_284-17.png 570w, https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_284-17-300x28.png 300w\" sizes=\"(max-width: 570px) 100vw, 570px\" \/><\/p>\n<p><strong>2. T\u1ed5 h\u1ee3p l\u1eb7p:<\/strong><\/p>\n<p>Cho t\u1eadp A = <img loading=\"lazy\" decoding=\"async\" width=\"111\" height=\"33\" class=\"wp-image-21163\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_285-18.png\" alt=\"IMG_285\" \/> v\u00e0 s\u1ed1 t\u1ef1 nhi\u00ean k b\u1ea5t k\u00ec. M\u1ed9t t\u1ed5 h\u1ee3p l\u1eb7p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed l\u00e0 m\u1ed9t h\u1ee3p g\u1ed3m k ph\u1ea7n t\u1eed, trong \u0111\u00f3 m\u1ed7i ph\u1ea7n t\u1eed l\u00e0 m\u1ed9t trong n ph\u1ea7n t\u1eed c\u1ee7a A.<\/p>\n<p>S\u1ed1 t\u1ed5 h\u1ee3p l\u1eb7p ch\u1eadp k c\u1ee7a n ph\u1ea7n t\u1eed: <img loading=\"lazy\" decoding=\"async\" width=\"161\" height=\"35\" class=\"wp-image-21164\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_286-17.png\" alt=\"IMG_286\" \/><\/p>\n<p><strong>3. Ph\u00e2n bi\u1ec7t ch\u1ec9nh h\u1ee3p v\u00e0 t\u1ed5 h\u1ee3p:<\/strong><\/p>\n<p>\u00b7 Ch\u1ec9nh h\u1ee3p v\u00e0 t\u1ed5 h\u1ee3p li\u00ean h\u1ec7 nhau b\u1edfi c\u00f4ng th\u1ee9c: <img loading=\"lazy\" decoding=\"async\" width=\"89\" height=\"32\" class=\"wp-image-21165\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_287-18.png\" alt=\"IMG_287\" \/><\/p>\n<p>\u00b7 Ch\u1ec9nh h\u1ee3p: c\u00f3 th\u1ee9 t\u1ef1.<\/p>\n<p>\u00b7 T\u1ed5 h\u1ee3p: kh\u00f4ng c\u00f3 th\u1ee9 t\u1ef1.<\/p>\n<p>\u00de Nh\u1eefng b\u00e0i to\u00e1n m\u00e0 k\u1ebft qu\u1ea3 ph\u1ee5 thu\u1ed9c v\u00e0o v\u1ecb tr\u00ed c\u00e1c ph\u1ea7n t\u1eed \u2013&gt; ch\u1ec9nh h\u1ee3p<\/p>\n<p>Ng\u01b0\u1ee3c l\u1ea1i, l\u00e0 t\u1ed5 h\u1ee3p.<\/p>\n<p>\u00b7 C\u00e1ch l\u1ea5y k ph\u1ea7n t\u1eed t\u1eeb t\u1eadp n ph\u1ea7n t\u1eed (k \u00a3 n):<\/p>\n<p>+ Kh\u00f4ng th\u1ee9 t\u1ef1, kh\u00f4ng ho\u00e0n l\u1ea1i: <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"32\" class=\"wp-image-21166\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_288-18.png\" alt=\"IMG_288\" \/><\/p>\n<p>+ C\u00f3 th\u1ee9 t\u1ef1, kh\u00f4ng ho\u00e0n l\u1ea1i: <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"32\" class=\"wp-image-21167\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_289-19.png\" alt=\"IMG_289\" \/><\/p>\n<p>+ C\u00f3 th\u1ee9 t\u1ef1, c\u00f3 ho\u00e0n l\u1ea1i: <img loading=\"lazy\" decoding=\"async\" width=\"29\" height=\"36\" class=\"wp-image-21168\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_290-18.png\" alt=\"IMG_290\" \/><\/p>\n<p><strong>Ph\u01b0\u01a1ng \u00e1n 2:<\/strong> \u0110\u1ebfm gi\u00e1n ti\u1ebfp (\u0111\u1ebfm ph\u1ea7n b\u00f9)<\/p>\n<p>Trong tr\u01b0\u1eddng h\u1ee3p h\u00e0nh \u0111\u1ed9ng <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"22\" class=\"wp-image-21169\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_291-18.png\" alt=\"IMG_291\" \/> chia nhi\u1ec1u tr\u01b0\u1eddng h\u1ee3p th\u00ec ta \u0111i \u0111\u1ebfm ph\u1ea7n b\u00f9 c\u1ee7a b\u00e0i to\u00e1n nh\u01b0 sau:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21170\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_292-18.png\" alt=\"IMG_292\" \/> \u0110\u1ebfm s\u1ed1 ph\u01b0\u01a1ng \u00e1n th\u1ef1c hi\u1ec7n h\u00e0nh \u0111\u1ed9ng <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"22\" class=\"wp-image-21171\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_293-18.png\" alt=\"IMG_293\" \/> (kh\u00f4ng c\u1ea7n quan t\u00e2m \u0111\u1ebfn c\u00f3 th\u1ecfa t\u00ednh ch\u1ea5t <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21172\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_294-18.png\" alt=\"IMG_294\" \/> hay kh\u00f4ng) ta \u0111\u01b0\u1ee3c <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"18\" class=\"wp-image-21173\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_295-17.png\" alt=\"IMG_295\" \/> ph\u01b0\u01a1ng \u00e1n.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21174\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_296-18.png\" alt=\"IMG_296\" \/> \u0110\u1ebfm s\u1ed1 ph\u01b0\u01a1ng \u00e1n th\u1ef1c hi\u1ec7n h\u00e0nh \u0111\u1ed9ng <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"22\" class=\"wp-image-21175\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_297-18.png\" alt=\"IMG_297\" \/> kh\u00f4ng th\u1ecfa t\u00ednh ch\u1ea5t <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21176\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_298-18.png\" alt=\"IMG_298\" \/> ta \u0111\u01b0\u1ee3c <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21177\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_299-18.png\" alt=\"IMG_299\" \/> ph\u01b0\u01a1ng \u00e1n.<\/p>\n<p>Khi \u0111\u00f3 s\u1ed1 ph\u01b0\u01a1ng \u00e1n th\u1ecfa y\u00eau c\u1ea7u b\u00e0i to\u00e1n l\u00e0: <img loading=\"lazy\" decoding=\"async\" width=\"43\" height=\"24\" class=\"wp-image-21178\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_300-18.png\" alt=\"IMG_300\" \/> .<\/p>\n<p>\u00a0<\/p>\n<h2><strong>B \u2013 B\u00c0I T\u1eacP<\/strong><\/h2>\n<h2><strong>D\u1ea0NG 1: B\u00c0I TO\u00c1N \u0110\u1ebeM<\/strong><\/h2>\n<p>\u00a0<\/p>\n<p><strong>Ph\u01b0\u01a1ng ph\u00e1p: <\/strong>D\u1ef1a v\u00e0o hai quy t\u1eafc c\u1ed9ng, quy t\u1eafc nh\u00e2n v\u00e0 c\u00e1c kh\u00e1i ni\u1ec7m ho\u00e1n v\u1ecb, ch\u1ec9nh h\u1ee3p, t\u1ed5 h\u1ee3p.<\/p>\n<p>M\u1ed9t s\u1ed1 d\u1ea5u hi\u1ec7u gi\u00fap ch\u00fang ta nh\u1eadn bi\u1ebft \u0111\u01b0\u1ee3c ho\u00e1n v\u1ecb, ch\u1ec9nh h\u1ee3p hay t\u1ed5 h\u1ee3p.<\/p>\n<p>1) <strong>Ho\u00e1n v\u1ecb:<\/strong> C\u00e1c d\u1ea5u hi\u1ec7u \u0111\u1eb7c tr\u01b0ng \u0111\u1ec3 gi\u00fap ta nh\u1eadn d\u1ea1ng m\u1ed9t ho\u00e1n v\u1ecb c\u1ee7a n ph\u1ea7n t\u1eed l\u00e0:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21179\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_301-18.png\" alt=\"IMG_301\" \/> T\u1ea5t c\u1ea3 n ph\u1ea7n t\u1eed \u0111\u1ec1u ph\u1ea3i c\u00f3 m\u1eb7t<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21180\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_302-18.png\" alt=\"IMG_302\" \/> M\u1ed7i ph\u1ea7n t\u1eed xu\u1ea5t hi\u1ec7n m\u1ed9t l\u1ea7n.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21181\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_303-18.png\" alt=\"IMG_303\" \/> C\u00f3 th\u1ee9 t\u1ef1 gi\u1eefa c\u00e1c ph\u1ea7n t\u1eed.<\/p>\n<p>2) <strong>Ch\u1ec9nh h\u1ee3p:<\/strong> Ta s\u1ebd s\u1eed d\u1ee5ng kh\u00e1i ni\u1ec7m ch\u1ec9nh h\u1ee3p khi<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21182\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_304-18.png\" alt=\"IMG_304\" \/> C\u1ea7n ch\u1ecdn k ph\u1ea7n t\u1eed t\u1eeb n ph\u1ea7n t\u1eed, m\u1ed7i ph\u1ea7n t\u1eed xu\u1ea5t hi\u1ec7n m\u1ed9t l\u1ea7n<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21183\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_305-18.png\" alt=\"IMG_305\" \/> k ph\u1ea7n t\u1eed \u0111\u00e3 cho \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp th\u1ee9 t\u1ef1.<\/p>\n<p>3) <strong>T\u1ed5 h\u1ee3p<\/strong>: Ta s\u1eed d\u1ee5ng kh\u00e1i ni\u1ec7m t\u1ed5 h\u1ee3p khi<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21184\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_306-18.png\" alt=\"IMG_306\" \/> C\u1ea7n ch\u1ecdn <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21185\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_307-18.png\" alt=\"IMG_307\" \/> ph\u1ea7n t\u1eed t\u1eeb n ph\u1ea7n t\u1eed, m\u1ed7i ph\u1ea7n t\u1eed xu\u1ea5t hi\u1ec7n m\u1ed9t l\u1ea7n<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"18\" class=\"wp-image-21186\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_308-18.png\" alt=\"IMG_308\" \/> Kh\u00f4ng quan t\u00e2m \u0111\u1ebfn th\u1ee9 t\u1ef1 k ph\u1ea7n t\u1eed \u0111\u00e3 ch\u1ecdn.<\/p>\n<p>\u00a0<\/p>\n<p><strong>C\u00e2u 1: <\/strong>T\u1eeb c\u00e1c s\u1ed1 0,1,2,3,4,5 c\u00f3 th\u1ec3 l\u1eadp \u0111\u01b0\u1ee3c bao nhi\u00eau s\u1ed1 t\u1ef1 m\u00e0 m\u1ed7i s\u1ed1 c\u00f3 6 ch\u1eef s\u1ed1 kh\u00e1c nhau v\u00e0 ch\u1eef s\u1ed1 2 \u0111\u1ee9ng c\u1ea1nh ch\u1eef s\u1ed1 3?<\/p>\n<p><strong>A. <\/strong>192<strong> B. <\/strong>202<strong> C. <\/strong>211<strong> D. <\/strong>180<\/p>\n<p><strong>C\u00e2u 2: <\/strong>C\u00f3 3 <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> n\u1eef v\u00e0 2 hs nam.Ta mu\u1ed1n s\u1eafp x\u1ebfp v\u00e0o m\u1ed9t b\u00e0n d\u00e0i c\u00f3 5 gh\u1ebf ng\u1ed3i. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch s\u1eafp x\u1ebfp \u0111\u1ec3 3 <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> n\u1eef ng\u1ed3i k\u1ec1 nhau<\/p>\n<p><strong>A. <\/strong>34<strong> B. <\/strong>46<strong> C. <\/strong>36<strong> D. <\/strong>26<\/p>\n<p><strong>C\u00e2u 3: <\/strong>C\u00f3 3 <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> n\u1eef v\u00e0 2 hs nam.Ta mu\u1ed1n s\u1eafp x\u1ebfp v\u00e0o m\u1ed9t b\u00e0n d\u00e0i c\u00f3 5 gh\u1ebf ng\u1ed3i. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch s\u1eafp x\u1ebfp \u0111\u1ec3 2 <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> nam ng\u1ed3i k\u1ec1 nhau.<\/p>\n<p><strong>A. <\/strong>48<strong> B. <\/strong>42<strong> C. <\/strong>58<strong> D. <\/strong>28<\/p>\n<p><strong>C\u00e2u 4: <\/strong>X\u1ebfp 6 ng\u01b0\u1eddi A, B, C, D, E, F v\u00e0o m\u1ed9t gh\u1ebf d\u00e0i.H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch s\u1eafp x\u1ebfp sao cho A v\u00e0 F ng\u1ed3i \u1edf hai \u0111\u1ea7u gh\u1ebf<\/p>\n<p><strong>A. <\/strong>48<strong> B. <\/strong>42<strong> C. <\/strong>46<strong> D. <\/strong>50<\/p>\n<p><strong>C\u00e2u 5: <\/strong>X\u1ebfp 6 ng\u01b0\u1eddi A, B, C, D, E, F v\u00e0o m\u1ed9t gh\u1ebf d\u00e0i.H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch s\u1eafp x\u1ebfp sao cho:<\/p>\n<p>A v\u00e0 F ng\u1ed3i c\u1ea1nh nhau<\/p>\n<p><strong>A. <\/strong>242<strong> B. <\/strong>240<strong> C. <\/strong>244<strong> D. <\/strong>248<\/p>\n<p><strong>C\u00e2u 6: <\/strong>X\u1ebfp 6 ng\u01b0\u1eddi A, B, C, D, E, F v\u00e0o m\u1ed9t gh\u1ebf d\u00e0i.H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch s\u1eafp x\u1ebfp sao cho:<\/p>\n<p>A v\u00e0 F kh\u00f4ng ng\u1ed3i c\u1ea1nh nhau<\/p>\n<p><strong>A. <\/strong>480<strong> B. <\/strong>460<strong> C. <\/strong>246<strong> D. <\/strong>260<\/p>\n<p><strong>C\u00e2u 7: <\/strong>Trong t\u1ee7 s\u00e1ch c\u00f3 t\u1ea5t c\u1ea3 <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21187\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_309-17.png\" alt=\"IMG_309\" \/> cu\u1ed1n s\u00e1ch. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch s\u1eafp x\u1ebfp sao cho quy\u1ec3n th\u1ee9 nh\u1ea5t \u1edf k\u1ec1 quy\u1ec3n th\u1ee9 hai:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"30\" height=\"24\" class=\"wp-image-21188\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_310-18.png\" alt=\"IMG_310\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"67\" height=\"24\" class=\"wp-image-21189\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_311-17.png\" alt=\"IMG_311\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"22\" height=\"24\" class=\"wp-image-21190\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_312-17.png\" alt=\"IMG_312\" \/><strong>.<\/strong> <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"53\" height=\"24\" class=\"wp-image-21191\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_313-17.png\" alt=\"IMG_313\" srcset=\"https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_313-17.png 53w, https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_313-17-50x24.png 50w\" sizes=\"(max-width: 53px) 100vw, 53px\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 8: <\/strong>C\u00f3 bao nhi\u00eau c\u00e1ch x\u1ebfp <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21192\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_314-17.png\" alt=\"IMG_314\" \/> s\u00e1ch V\u0103n kh\u00e1c nhau v\u00e0 <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21193\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_315-17.png\" alt=\"IMG_315\" \/> s\u00e1ch To\u00e1n kh\u00e1c nhau tr\u00ean m\u1ed9t k\u1ec7 s\u00e1ch d\u00e0i n\u1ebfu c\u00e1c s\u00e1ch V\u0103n ph\u1ea3i x\u1ebfp k\u1ec1 nhau?<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"43\" height=\"24\" class=\"wp-image-21194\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_316-17.png\" alt=\"IMG_316\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"59\" height=\"24\" class=\"wp-image-21195\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_317-17.png\" alt=\"IMG_317\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"43\" height=\"24\" class=\"wp-image-21196\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_318-17.png\" alt=\"IMG_318\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"30\" height=\"24\" class=\"wp-image-21197\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_319-17.png\" alt=\"IMG_319\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 9: <\/strong>T\u1eeb c\u00e1c s\u1ed1 <img loading=\"lazy\" decoding=\"async\" width=\"97\" height=\"28\" class=\"wp-image-21198\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_320-17.png\" alt=\"IMG_320\" \/> c\u00f3 th\u1ec3 l\u1eadp \u0111\u01b0\u1ee3c bao nhi\u00eau s\u1ed1 t\u1ef1 nhi\u00ean,m\u1ed7i s\u1ed1 c\u00f3 6 ch\u1eef s\u1ed1 \u0111\u1ed3ng th\u1eddi th\u1ecfa \u0111i\u1ec1u ki\u1ec7n :s\u00e1u s\u1ed1 c\u1ee7a m\u1ed7i s\u1ed1 l\u00e0 kh\u00e1c nhau v\u00e0 trong m\u1ed7i s\u1ed1 \u0111\u00f3 t\u1ed5ng c\u1ee7a 3 ch\u1eef s\u1ed1 \u0111\u1ea7u nh\u1ecf h\u01a1n t\u1ed5ng c\u1ee7a 3 s\u1ed1 sau m\u1ed9t \u0111\u01a1n v\u1ecb.<\/p>\n<p><strong>A. <\/strong>104<strong> B. <\/strong>106<strong> C. <\/strong>108<strong> D. <\/strong>112<\/p>\n<p><strong>C\u00e2u 10: <\/strong>T\u1eeb c\u00e1c s\u1ed1 <img loading=\"lazy\" decoding=\"async\" width=\"45\" height=\"28\" class=\"wp-image-21199\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_321-16.png\" alt=\"IMG_321\" \/> l\u1eadp \u0111\u01b0\u1ee3c bao nhi\u1ec1u s\u1ed1 t\u1ef1 nhi\u00ean g\u00f4m <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21200\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_322-16.png\" alt=\"IMG_322\" \/> ch\u1eef s\u1ed1 th\u1ecfa m\u00e3n \u0111\u1ed3ng th\u1eddi hai \u0111i\u1ec1u ki\u1ec7n sau: Trong m\u1ed7i s\u1ed1, hai ch\u1eef s\u1ed1 gi\u1ed1ng nhau kh\u00f4ng \u0111\u1ee9ng c\u1ea1nh nhau.<\/p>\n<p><strong>A. <\/strong>76<strong> B. <\/strong>42<strong> C. <\/strong>80<strong> D. <\/strong>68<\/p>\n<h2><strong>D\u1ea0NG 2: X\u1ebeP V\u1eca TR\u00cd \u2013 C\u00c1CH CH\u1eccN, PH\u00c2N C\u00d4NG C\u00d4NG VI\u1ec6C..<\/strong><\/h2>\n<p>\u00a0<\/p>\n<p><strong>C\u00e2u 1: <\/strong>M\u1ed9t li\u00ean \u0111o\u00e0n b\u00f3ng r\u1ed5 c\u00f3 <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21201\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_398-7.png\" alt=\"IMG_398\" \/> \u0111\u1ed9i, m\u1ed7i \u0111\u1ed9i \u0111\u1ea5u v\u1edbi m\u1ed7i \u0111\u1ed9i kh\u00e1c hai l\u1ea7n, m\u1ed9t l\u1ea7n \u1edf s\u00e2n nh\u00e0 v\u00e0 m\u1ed9t l\u1ea7n \u1edf s\u00e2n kh\u00e1ch. S\u1ed1 tr\u1eadn \u0111\u1ea5u \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp l\u00e0:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21202\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_399-7.png\" alt=\"IMG_399\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"25\" height=\"24\" class=\"wp-image-21203\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_400-7.png\" alt=\"IMG_400\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21204\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_401-7.png\" alt=\"IMG_401\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21205\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_402-7.png\" alt=\"IMG_402\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 2: <\/strong>M\u1ed9t li\u00ean \u0111o\u00e0n b\u00f3ng r\u1ed5 c\u00f3 <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21206\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_403-7.png\" alt=\"IMG_403\" \/> \u0111\u1ed9i, m\u1ed7i \u0111\u1ed9i \u0111\u1ea5u v\u1edbi m\u1ed7i \u0111\u1ed9i kh\u00e1c hai l\u1ea7n, m\u1ed9t l\u1ea7n \u1edf s\u00e2n nh\u00e0 v\u00e0 m\u1ed9t l\u1ea7n \u1edf s\u00e2n kh\u00e1ch. S\u1ed1 tr\u1eadn \u0111\u1ea5u \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp l\u00e0:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21207\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_404-7.png\" alt=\"IMG_404\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"25\" height=\"24\" class=\"wp-image-21208\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_405-7.png\" alt=\"IMG_405\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21209\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_406-7.png\" alt=\"IMG_406\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21210\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_407-7.png\" alt=\"IMG_407\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 3: <\/strong>M\u1ed9t li\u00ean \u0111o\u00e0n b\u00f3ng \u0111\u00e1 c\u00f3 <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21211\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_408-7.png\" alt=\"IMG_408\" \/> \u0111\u1ed9i, m\u1ed7i \u0111\u1ed9i ph\u1ea3i \u0111\u00e1 <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21212\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_409-7.png\" alt=\"IMG_409\" \/> tr\u1eadn v\u1edbi m\u1ed7i \u0111\u1ed9i kh\u00e1c, <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21213\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_410-7.png\" alt=\"IMG_410\" \/> tr\u1eadn \u1edf s\u00e2n nh\u00e0 v\u00e0 <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21214\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_411-7.png\" alt=\"IMG_411\" \/> tr\u1eadn \u1edf s\u00e2n kh\u00e1ch. S\u1ed1 tr\u1eadn \u0111\u1ea5u \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp l\u00e0:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21215\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_412-7.png\" alt=\"IMG_412\" \/> <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21216\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_413-7.png\" alt=\"IMG_413\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"25\" height=\"24\" class=\"wp-image-21217\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_414-7.png\" alt=\"IMG_414\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21218\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_415-7.png\" alt=\"IMG_415\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 4: <\/strong>Gi\u1ea3 s\u1eed ta d\u00f9ng <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21219\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_416-7.png\" alt=\"IMG_416\" \/> m\u00e0u \u0111\u1ec3 t\u00f4 cho <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21220\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_417-7.png\" alt=\"IMG_417\" \/> n\u01b0\u1edbc kh\u00e1c nhau tr\u00ean b\u1ea3n \u0111\u1ed3 v\u00e0 kh\u00f4ng c\u00f3 m\u00e0u n\u00e0o \u0111\u01b0\u1ee3c d\u00f9ng hai l\u1ea7n. S\u1ed1 c\u00e1c c\u00e1ch \u0111\u1ec3 ch\u1ecdn nh\u1eefng m\u00e0u c\u1ea7n d\u00f9ng l\u00e0:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"25\" height=\"53\" class=\"wp-image-21221\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_418-7.png\" alt=\"IMG_418\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21222\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_419-6.png\" alt=\"IMG_419\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"43\" height=\"53\" class=\"wp-image-21223\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_420-6.png\" alt=\"IMG_420\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"22\" height=\"28\" class=\"wp-image-21224\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_421-6.png\" alt=\"IMG_421\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 5: <\/strong>Sau b\u1eefa ti\u1ec7c, m\u1ed7i ng\u01b0\u1eddi b\u1eaft tay m\u1ed9t l\u1ea7n v\u1edbi m\u1ed7i ng\u01b0\u1eddi kh\u00e1c trong ph\u00f2ng. C\u00f3 t\u1ea5t c\u1ea3 <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21225\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_422-6.png\" alt=\"IMG_422\" \/> ng\u01b0\u1eddi l\u1ea7n l\u01b0\u1ee3t b\u1eaft tay. H\u1ecfi trong ph\u00f2ng c\u00f3 bao nhi\u00eau ng\u01b0\u1eddi:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"22\" height=\"22\" class=\"wp-image-21226\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_423-6.png\" alt=\"IMG_423\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"22\" class=\"wp-image-21227\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_424-6.png\" alt=\"IMG_424\" \/><strong>.<\/strong> <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"25\" height=\"24\" class=\"wp-image-21228\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_425-6.png\" alt=\"IMG_425\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21229\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_426-6.png\" alt=\"IMG_426\" \/> .<\/p>\n<p><strong>C\u00e2u 6: <\/strong>T\u00ean <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21230\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_427-6.png\" alt=\"IMG_427\" \/> <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> \u0111\u01b0\u1ee3c ghi v\u00e0o <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21231\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_428-6.png\" alt=\"IMG_428\" \/> t\u1edd gi\u1ea5y \u0111\u1ec3 v\u00e0o trong h\u1ed9p. Ch\u1ecdn t\u00ean <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21232\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_429-6.png\" alt=\"IMG_429\" \/> <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> \u0111\u1ec3 cho \u0111i du l\u1ecbch. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch ch\u1ecdn c\u00e1c <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a>:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"22\" height=\"24\" class=\"wp-image-21233\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_430-5.png\" alt=\"IMG_430\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"29\" height=\"24\" class=\"wp-image-21234\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_431-5.png\" alt=\"IMG_431\" \/><strong>.<\/strong> <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"43\" height=\"24\" class=\"wp-image-21235\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_432-5.png\" alt=\"IMG_432\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"55\" height=\"24\" class=\"wp-image-21236\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_433-5.png\" alt=\"IMG_433\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 7: <\/strong>M\u1ed9t h\u1ed9i \u0111\u1ed3ng g\u1ed3m <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21237\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_434-5.png\" alt=\"IMG_434\" \/> gi\u00e1o vi\u00ean v\u00e0 <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21238\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_435-5.png\" alt=\"IMG_435\" \/> h\u1ecdc sinh \u0111\u01b0\u1ee3c ch\u1ecdn t\u1eeb m\u1ed9t nh\u00f3m <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21239\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_436-5.png\" alt=\"IMG_436\" \/> gi\u00e1o vi\u00ean v\u00e0 <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21240\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_437-5.png\" alt=\"IMG_437\" \/> h\u1ecdc sinh. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch ch\u1ecdn?<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"37\" height=\"24\" class=\"wp-image-21241\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_438-5.png\" alt=\"IMG_438\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21242\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_439-5.png\" alt=\"IMG_439\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21243\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_440-5.png\" alt=\"IMG_440\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21244\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_441-5.png\" alt=\"IMG_441\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 8: <\/strong>M\u1ed9t t\u1ed5 g\u1ed3m <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"22\" class=\"wp-image-21245\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_442-5.png\" alt=\"IMG_442\" \/> h\u1ecdc sinh trong \u0111\u00f3 c\u00f3 b\u1ea1n An. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch ch\u1ecdn <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21246\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_443-5.png\" alt=\"IMG_443\" \/> em \u0111i tr\u1ef1c trong \u0111\u00f3 ph\u1ea3i c\u00f3 An:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"35\" height=\"24\" class=\"wp-image-21247\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_444-5.png\" alt=\"IMG_444\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"37\" height=\"24\" class=\"wp-image-21248\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_445-5.png\" alt=\"IMG_445\" \/> . <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"37\" height=\"24\" class=\"wp-image-21249\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_446-4.png\" alt=\"IMG_446\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"33\" height=\"24\" class=\"wp-image-21250\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_447-4.png\" alt=\"IMG_447\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 9: <\/strong>T\u1eeb m\u1ed9t nh\u00f3m <img loading=\"lazy\" decoding=\"async\" width=\"15\" height=\"24\" class=\"wp-image-21251\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_448-4.png\" alt=\"IMG_448\" \/> ng\u01b0\u1eddi, ch\u1ecdn ra c\u00e1c nh\u00f3m \u00edt nh\u1ea5t <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21252\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_449-3.png\" alt=\"IMG_449\" \/> ng\u01b0\u1eddi. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch ch\u1ecdn:<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21253\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_450-3.png\" alt=\"IMG_450\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"28\" height=\"24\" class=\"wp-image-21254\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_451-3.png\" alt=\"IMG_451\" \/><strong>.<\/strong> <strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"24\" height=\"24\" class=\"wp-image-21255\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_452-3.png\" alt=\"IMG_452\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"25\" height=\"24\" class=\"wp-image-21256\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_453-3.png\" alt=\"IMG_453\" \/><strong>.<\/strong><\/p>\n<p><strong>C\u00e2u 10: <\/strong>M\u1ed9t t\u1ed5 g\u1ed3m <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21257\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_454-3.png\" alt=\"IMG_454\" \/> nam v\u00e0 <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"24\" class=\"wp-image-21258\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_455-3.png\" alt=\"IMG_455\" \/> n\u1eef. H\u1ecfi c\u00f3 bao nhi\u00eau c\u00e1ch ch\u1ecdn <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21259\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_456-3.png\" alt=\"IMG_456\" \/> em \u0111i tr\u1ef1c sao cho c\u00f3 \u00edt nh\u1ea5t <img loading=\"lazy\" decoding=\"async\" width=\"18\" height=\"22\" class=\"wp-image-21260\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_457-3.png\" alt=\"IMG_457\" \/> n\u1eef?<\/p>\n<p><strong>A. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"215\" height=\"37\" class=\"wp-image-21261\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_458-3.png\" alt=\"IMG_458\" \/> . <strong>B. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"188\" height=\"37\" class=\"wp-image-21262\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_459-3.png\" alt=\"IMG_459\" \/> .<\/p>\n<p><strong>C. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"59\" height=\"32\" class=\"wp-image-21263\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_460-3.png\" alt=\"IMG_460\" \/> . <strong>D. <\/strong> <img loading=\"lazy\" decoding=\"async\" width=\"157\" height=\"32\" class=\"wp-image-21264\" src=\"https:\/\/www.vietlearn.org\/post\/wp-content\/uploads\/2021\/12\/img_461-3.png\" alt=\"IMG_461\" srcset=\"https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_461-3.png 157w, https:\/\/www.vietlearn.org\/kien-thuc\/wp-content\/uploads\/2021\/12\/img_461-3-150x32.png 150w\" sizes=\"(max-width: 157px) 100vw, 157px\" \/><strong>.<\/strong><\/p>","protected":false},"excerpt":{"rendered":"<p>A \u2013 L\u00dd THUY\u1ebeT T\u00d3M T\u1eaeT I. Ho\u00e1n v\u1ecb 1. Giai th\u1eeba: Qui \u01b0\u1edbc: (v\u1edbi ) (v\u1edbi ) 2. Ho\u00e1n v\u1ecb (kh\u00f4ng l\u1eb7p): M\u1ed9t t\u1eadp h\u1ee3p g\u1ed3m n ph\u1ea7n t\u1eed (n \u00b3 1). M\u1ed7i c\u00e1ch s\u1eafp x\u1ebfp n ph\u1ea7n t\u1eed n\u00e0y theo m\u1ed9t th\u1ee9 t\u1ef1 n\u00e0o \u0111\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u1ed9t ho\u00e1n v\u1ecb c\u1ee7a n [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[42],"tags":[],"class_list":["post-21133","post","type-post","status-publish","format-standard","hentry","category-toan-lop-11"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/21133","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=21133"}],"version-history":[{"count":1,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/21133\/revisions"}],"predecessor-version":[{"id":21265,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/21133\/revisions\/21265"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=21133"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=21133"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=21133"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}