04/11/12 17:51:58
>>563(4) できそうで．．．
左辺－右辺 = (a^2)(b-c)/c - (b^2)(a-c)/a + (c^2)(a-b)/b
= a(a-c)(b-c)/c + b(a-b)(a-c)/a -c(b-c)(a-b)/b
= (a/c)(b-c)^2 + (b/a)(a-b)^2 + {a/c +b/a -c/b}(b-c)(a-b)
= (a/c)(b-c)^2 + (b/a)(a-b)^2 + {(a/c-1)+(b/a)+(1-c/b)}(b-c)(a-b)≧0.
ぬるぽ