(b-c)(c-a)分之a-b +(c-a)(a-b)分之b-c +(a-b)(b-c)分之c-a的值能否为0
问题描述:
(b-c)(c-a)分之a-b +(c-a)(a-b)分之b-c +(a-b)(b-c)分之c-a的值能否为0
答
(b-c)(c-a)分之a-b +(c-a)(a-b)分之b-c +(a-b)(b-c)分之c-a=(a-b)/(b-c)(c-a)-(b-c)/(a-c)(a-b)-(a-c)/(a-b)(b-c)=[(a-b)²-(b-c)²-(a-c)²]/[(a-b)(b-c)(a-c)]=(a²-2ab+b²-b²+2bc-c&...