Cho tam gi\u00e1c ABC (nh\u01b0 h\u00ecnh v\u1ebd) g\u00f3c C = 90o. Gi\u1ea3 s\u1eed BC = a; AC = b (a < b); AB = c, ta c\u00f3 a2 + b2 = c2. \u1edf ph\u01b0\u01a1ng T\u00e2y ng\u01b0\u1eddi ta g\u1ecdi \u0111\u00e2y l\u00e0 \u0111\u1ecbnh l\u00ed Pithagore, c\u00f2n \u1edf Trung Qu\u1ed1c ng\u01b0\u1eddi ta g\u1ecdi l\u00e0 \u201c\u0110\u1ecbnh l\u00ed tam gi\u00e1c\u201d. V\u00ec sao v\u1eady?<\/p>\n\n\n\n
Nguy\u00ean nh\u00e2n l\u00e0 \u1edf ph\u01b0\u01a1ng T\u00e2y ng\u01b0\u1eddi ta cho r\u1eb1ng \u0111\u1ecbnh l\u00ed n\u00e0y \u0111\u01b0\u1ee3c Pitago ph\u00e1t minh v\u00e0o kho\u1ea3ng 500 n\u0103m tr\u01b0\u1edbc C\u00f4ng nguy\u00ean, s\u1edbm h\u01a1n \u1edf Trung Qu\u1ed1c. Th\u1ebf nh\u01b0ng \u1edf Trung Qu\u1ed1c trong s\u00e1ch \u201cChu b\u00ec to\u00e1n kinh\u201d \u0111\u00e3 ghi l\u1ea1i c\u00e2u chuy\u1ec7n trao \u0111\u1ed5i gi\u1eefa Chu C\u00f4ng v\u00e0 Th\u01b0\u01a1ng Dao trong \u0111\u00f3 c\u00f3 n\u00eau b\u1eadt m\u1ed1i t\u01b0\u01a1ng quan gi\u1eefa ba c\u1ea1nh m\u1ed9t tam gi\u00e1c vu\u00f4ng t\u1ec9 l\u1ec7 v\u1edbi ba s\u1ed1: a: b: c = 3 : 4 : 5 (nh\u01b0 h\u00ecnh v\u1ebd). M\u00e0 Chu C\u00f4ng v\u00e0 Th\u01b0\u01a1ng Dao l\u00e0 v\u00e0o kho\u1ea3ng th\u1ebf k\u1ec9 XII tr\u01b0\u1edbc C\u00f4ng nguy\u00ean, so v\u1edbi Pithagore th\u00ec s\u1edbm h\u01a1n nhi\u1ec1u. Do \u0111\u00f3 \u0111\u00e3 c\u00f3 nhi\u1ec1u ng\u01b0\u1eddi Trung Qu\u1ed1c g\u1ecdi \u0111\u1ecbnh l\u00ed Pitago l\u00e0 \u0111\u1ecbnh l\u00ed tam gi\u00e1c thay cho t\u00ean \u0111\u1ecbnh l\u00ed Pitago.<\/p>\n\n\n\n
T\u1eeb kho\u00e1: \u0110\u1ecbnh l\u00ed Pitago, \u0111\u1ecbnh l\u00ed tam gi\u00e1c.<\/p>\n\n\n\n
<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"
Cho tam gi\u00e1c ABC (nh\u01b0 h\u00ecnh v\u1ebd) g\u00f3c C = 90o. Gi\u1ea3 s\u1eed BC = a; AC = b (a < b); AB = c, ta c\u00f3 a2 + b2 = c2. \u1edf ph\u01b0\u01a1ng T\u00e2y ng\u01b0\u1eddi ta g\u1ecdi \u0111\u00e2y l\u00e0 \u0111\u1ecbnh l\u00ed Pithagore, c\u00f2n \u1edf Trung Qu\u1ed1c ng\u01b0\u1eddi ta g\u1ecdi l\u00e0 \u201c\u0110\u1ecbnh l\u00ed tam gi\u00e1c\u201d. […]<\/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":[15,9],"tags":[],"class_list":["post-7652","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-toan-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7652","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=7652"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7652\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=7652"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=7652"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=7652"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}