(a-b-c)的平分等于多少 （A-B+C）^2等于多少
\u5316\u7b80a(b-c)-b(c-a)+c(a-b)\u7ed3\u679c\u662f\u591a\u5c11\uff0c\u6c42\u8fc7\u7a0b\uff01\uff01\u89e3: a(b-c)-b(c-a)+c(a-b)
=ab-ac-bc+ab+ac-bc
=2ab-2bc
\u795d\u4f60\u5b66\u4e60\u8fdb\u6b65,\u5982\u6709\u4e0d\u660e\u53ef\u4ee5\u8ffd\u95ee.\u540c\u610f\u6211\u7684\u7b54\u6848\u8bf7\u91c7\u7eb3,O(\u2229_\u2229)O\u8c22\u8c22
(a-b+c)*(a-b+c)=a*(a-b+c)-b*(a-b+c)+c*(a-b+c)
=a&2-ab+ac-ab+b&2-bc+ac-bc+c&2
=a&2+b&2+c&2-2ab+2ac-2bc
\u5475\u5475\u795d\u4f60\u5b66\u4e60\u6109\u5feb\uff01
=(a-b)^2+c^2-2(a-b)c
=a^2+b^2-2ab+c^2-2ac+2bc
=a^2+b^2+c^2-2ab-2ac+2bc
1887415157
绛旓細鍚勮嚜鐨勫钩鏂鍜屼笌鐩镐簰闂翠箻绉殑浜屽嶃锛坅+b-c)^2=a^2+b^2+c^2+2ab-2ac-2bc.
绛旓細鍚勮嚜鐨勫钩鏂鍜屼笌鐩镐簰闂翠箻绉殑浜屽嶃锛坅+b-c)^2=a^2+b^2+c^2+2ab-2ac-2bc銆傘愬钩鏂瑰拰鍏紡銆戝钩鏂瑰拰鍏紡鏄竴涓瘮杈冨父鐢ㄥ叕寮忥紝鐢ㄤ簬姹傝繛缁嚜鐒舵暟鐨勫钩鏂瑰拰锛圫um of squares锛夛紝鍙敤鏉ユ眰寰堝鍏充簬骞虫柟鏁扮殑鏁板棰橈紝鍏跺拰鍙堝彲绉颁箣涓哄洓瑙掗敟鏁帮紝鎴栭噾瀛楀鏁帮紙square pyramidal number锛変篃灏辨槸姝ｆ柟褰㈡暟鐨...
绛旓細骞虫柟锛歛鐨勫钩鏂琛ㄧずa脳a,绠鍐欐垚a^2 鎵浠ワ紙a+b-c锛骞虫柟 =锛坅+b-c)^2 =a^2 +ab -ac +ab -bc +b^2 -ca -cb +c^2 =a^2 +2ab -2ac -2bc +c^2 骞虫柟宸細a²-b²=(a+b)(a-b)銆傛枃瀛楄〃杈惧紡锛氫袱涓暟鐨勫拰涓庤繖涓や釜鏁扮殑宸殑绉绛変簬杩欎袱涓暟鐨勫钩鏂瑰樊銆傛爣鍑嗗樊锛...
绛旓細=[(a-b)+c]²=(a-b)²+2(a-b)c+c²=a²-2ab+b²+2ac-2bc+c²=a²+b²+c²-2ab+2ac-2bc 1銆佸畬鍏ㄥ钩鏂瑰樊鍏紡锛(a-b)²=a²-2ab+b²瀹屽叏骞虫柟宸細涓ゆ暟宸鐨勫钩鏂锛绛変簬瀹冧滑鐨勫钩鏂瑰拰锛屽噺鍘诲畠浠殑绉殑2鍊嶅嵆瀹屽叏...
绛旓細鍒嗚В涓猴細锛坅+b-c锛(a-b+c)
绛旓細浠涔堟槸a鍑b鍔c鐨勫钩鏂锛熷湪浠ｆ暟瀛︿腑锛宎鍑廱鍔燾鐨勫钩鏂规槸涓涓畝鍗曡屽熀鏈殑鏂圭▼寮忥紝瀹冨彲浠ユ媶瑙ｄ负涓ら儴鍒嗭細鍦╝鍜宐涔嬮棿鍙栧钩鍧囨暟锛岀劧鍚庡皢骞冲潎鏁板钩鏂瑰悗鍜宑鐩稿姞銆傝繖涓柟绋嬪彲浠ョ敤浜庡悇绉嶈绠椾腑锛屼緥濡傚嚑浣曘佺墿鐞嗗拰閲戣瀺瀛︺傚浣曡绠梐鍑廱鍔燾鐨勫钩鏂癸紵瑕佽绠梐鍑廱鍔燾鐨勫钩鏂癸紝鎴戜滑闇瑕侀鍏堣绠楀钩鍧囨暟銆傚钩鍧囨暟 = (a+b...
绛旓細=(a+b+c)鐨勫钩鏂=:A鐨勫钩鏂+B鐨勫钩鏂+C鐨勫钩鏂+2AC+2BC+2AB
绛旓細=[(a-b)+c]²=(a-b)²+2(a-b)c+c²=a²-2ab+b²+2ac-2bc+c²=a²+b²+c²-2ab+2ac-2bc
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