V\u1edbi ng\u01b0\u1eddi kh\u00f4ng c\u00f3 kinh nghi\u1ec7m \u0111i bi\u1ec3n ho\u1eb7c kh\u00f4ng h\u1ecdc v\u1eadt l\u00fd th\u00ec vi\u1ec7c thuy\u1ec1n bu\u1ed3m c\u00f3 th\u1ec3 b\u01a1i ng\u01b0\u1ee3c gi\u00f3 th\u1eadt kh\u00f3 t\u01b0\u1edfng t\u01b0\u1ee3ng. Th\u1ef1c ra, thuy\u1ec1n kh\u00f4ng th\u1ec3 \u0111i ng\u01b0\u1ee3c h\u01b0\u1edbng gi\u00f3 ho\u00e0n to\u00e0n, nh\u01b0ng ch\u1ec7ch m\u1ed9t g\u00f3c nh\u1ecf th\u00ec c\u00f3 th\u1ec3.<\/p>\n\n\n\n
Mu\u1ed1n hi\u1ec3u v\u1ea5n \u0111\u1ec1, ch\u00fang ta h\u00e3y t\u00ecm hi\u1ec3u l\u1ef1c gi\u00f3 t\u00e1c d\u1ee5ng l\u00ean bu\u1ed3m nh\u01b0 th\u1ebf n\u00e0o? Nhi\u1ec1u ng\u01b0\u1eddi ngh\u0129 r\u1eb1ng, c\u00e1nh bu\u1ed3m \u0111\u01b0\u1ee3c \u0111\u1ea9y theo chi\u1ec1u gi\u00f3 th\u1ed5i, nh\u01b0ng th\u1ef1c t\u1ebf kh\u00f4ng ph\u1ea3i v\u1eady: D\u00f9 gi\u00f3 c\u00f3 th\u1ed5i theo h\u01b0\u1edbng n\u00e0o th\u00ec n\u00f3 c\u0169ng ch\u1ec9 \u0111\u1ea9y bu\u1ed3m theo ph\u01b0\u01a1ng th\u1eb3ng g\u00f3c v\u1edbi m\u1eb7t ph\u1eb3ng c\u1ee7a bu\u1ed3m m\u00e0 th\u00f4i! (h\u00ecnh 1)<\/p>\n\n\n\n
Trong h\u00ecnh 1, \u0111\u01b0\u1eddng th\u1eb3ng AB bi\u1ec3u di\u1ec5n c\u00e1nh bu\u1ed3m. R l\u00e0 l\u1ef1c \u0111\u1ea9y c\u1ee7a gi\u00f3 t\u00e1c d\u1ee5ng v\u00e0o c\u00e1nh bu\u1ed3m. Ta ph\u00e2n t\u00edch l\u1ef1c R th\u00e0nh hai ph\u1ea9n, g\u1ed3m l\u1ef1c Q vu\u00f4ng g\u00f3c v\u1edbi c\u00e1nh bu\u1ed3m v\u00e0 l\u1ef1c P h\u01b0\u1edbng d\u1ecdc theo n\u00f3. V\u00ec s\u1ef1 ma s\u00e1t c\u1ee7a gi\u00f3 v\u1edbi c\u00e1nh bu\u1ed3m l\u00e0 kh\u00f4ng \u0111\u00e1ng k\u1ec3, n\u00ean l\u1ef1c P ch\u1ec9 tr\u01b0\u1ee3t qua ch\u1ee9 kh\u00f4ng t\u00e1c d\u1ee5ng g\u00ec t\u1edbi bu\u1ed3m. Ch\u1ec9 c\u00f3 l\u1ef1c Q \u0111\u1ea9y c\u00e1nh bu\u1ed3m theo h\u01b0\u1edbng vu\u00f4ng g\u00f3c v\u1edbi m\u1eb7t bu\u1ed3m.<\/p>\n\n\n\n
N\u1ebfu hi\u1ec3u \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1 tr\u00ean, b\u1ea1n c\u0169ng c\u00f3 th\u1ec3 hi\u1ec3u t\u1ea1i sao thuy\u1ec1n c\u00f3 bu\u1ed3m c\u00f3 th\u1ec3 \u0111i ng\u01b0\u1ee3c m\u1ed9t g\u00f3c nh\u1ecdn v\u1edbi chi\u1ec1u gi\u00f3. (h\u00ecnh 2)<\/p>\n\n\n\n
Gi\u1ea3 s\u1eed \u0111o\u1ea1n th\u1eb3ng KK bi\u1ec3u di\u1ec5n chi\u1ec1u d\u00e0i c\u1ee7a thuy\u1ec1n. \u0110\u01b0\u1eddng th\u1eb3ng AB bi\u1ec3u di\u1ec5n c\u00e1nh bu\u1ed3m. Ng\u01b0\u1eddi ta h\u01b0\u1edbng c\u00e1nh bu\u1ed3m sao cho m\u1eb7t ph\u1eb3ng c\u1ee7a n\u00f3 chia \u0111\u00f4i g\u00f3c gi\u1eefa ph\u01b0\u01a1ng c\u1ee7a l\u00f2ng thuy\u1ec1n v\u00e0 ph\u01b0\u01a1ng c\u1ee7a gi\u00f3. B\u00e2y gi\u1edd b\u1ea1n h\u00e3y theo d\u00f5i bi\u1ec3u \u0111\u1ed3 ph\u00e2n t\u00edch l\u1ef1c \u1edf h\u00ecnh 2, trong \u0111\u00f3 Q l\u00e0 \u00e1p l\u1ef1c c\u1ee7a gi\u00f3 t\u00e1c d\u1ee5ng l\u00ean c\u00e1nh bu\u1ed3m.<\/p>\n\n\n\n
Nh\u01b0 \u0111\u00e3 ph\u00e2n t\u00edch \u1edf h\u00ecnh 1, l\u1ef1c Q ph\u1ea3i vu\u00f4ng g\u00f3c v\u1edbi c\u00e1nh bu\u1ed3m. L\u1ef1c Q l\u1ea1i c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia th\u00e0nh hai l\u1ef1c: l\u1ef1c S d\u1ecdc theo m\u0169i thuy\u1ec1n v\u00e0 l\u1ef1c R vu\u00f4ng g\u00f3c v\u1edbi chi\u1ec1u d\u00e0i thuy\u1ec1n. V\u00ec chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a thuy\u1ec1n theo h\u01b0\u1edbng R b\u1ecb n\u01b0\u1edbc c\u1ea3n l\u1ea1i r\u1ea5t m\u1ea1nh (thuy\u1ec1n bu\u1ed3m th\u01b0\u1eddng c\u00f3 l\u00f2ng r\u1ea5t s\u00e2u), n\u00ean l\u1ef1c R ho\u00e0n to\u00e0n b\u1ecb l\u1ef1c c\u1ea3n c\u1ee7a n\u01b0\u1edbc c\u00e2n b\u1eb1ng. Do \u0111\u00f3, ch\u1ec9 c\u00f3 S l\u00e0 l\u1ef1c h\u01b0\u1edbng t\u1edbi ph\u00eda tr\u01b0\u1edbc, gi\u00fap thuy\u1ec1n c\u00f3 th\u1ec3 chuy\u1ec3n \u0111\u1ed9ng ng\u01b0\u1ee3c m\u1ed9t g\u00f3c nh\u1ecf v\u1edbi chi\u1ec1u gi\u00f3. (h\u00ecnh 3) Th\u1ef1c t\u1ebf (h\u00ecnh 3), \u0111\u1ec3 \u0111\u01b0a thuy\u1ec1n t\u1eeb \u0111i\u1ec3m A \u0111\u1ebfn \u0111i\u1ec3m B, ng\u01b0\u1ee3c chi\u1ec1u gi\u00f3, ng\u01b0\u1eddi ta ph\u1ea3i h\u01b0\u1edbng thuy\u1ec1n bu\u1ed3m \u0111i theo \u0111\u01b0\u1eddng zic zac.<\/p>\n","protected":false},"excerpt":{"rendered":"
V\u1edbi ng\u01b0\u1eddi kh\u00f4ng c\u00f3 kinh nghi\u1ec7m \u0111i bi\u1ec3n ho\u1eb7c kh\u00f4ng h\u1ecdc v\u1eadt l\u00fd th\u00ec vi\u1ec7c thuy\u1ec1n bu\u1ed3m c\u00f3 th\u1ec3 b\u01a1i ng\u01b0\u1ee3c gi\u00f3 th\u1eadt kh\u00f3 t\u01b0\u1edfng t\u01b0\u1ee3ng. Th\u1ef1c ra, thuy\u1ec1n kh\u00f4ng th\u1ec3 \u0111i ng\u01b0\u1ee3c h\u01b0\u1edbng gi\u00f3 ho\u00e0n to\u00e0n, nh\u01b0ng ch\u1ec7ch m\u1ed9t g\u00f3c nh\u1ecf th\u00ec c\u00f3 th\u1ec3. Mu\u1ed1n hi\u1ec3u v\u1ea5n \u0111\u1ec1, ch\u00fang ta h\u00e3y t\u00ecm hi\u1ec3u l\u1ef1c […]<\/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":[1,15],"tags":[],"class_list":["post-10938","post","type-post","status-publish","format-standard","hentry","category-general","category-hoi-dap-khoa-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10938","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=10938"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10938\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=10938"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=10938"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=10938"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}