数学证明题:(1)(a/b+b/c+c/a)(b/a+c/b+a
证明题: (1)(a/b+b/c+c/a)(b/a+c/b+a/c)>=9 (2)(a+b+c)(a^2+b^2+c^2)>=9abc
 (a/b+b/c+c/a)(b/a+c/b+a/c) ≥ 3•³√[(a/b)(b/c)(c/a)]×3•³√[(b/a)(c/b)(a/c)] = 9  (a+b+c)(a²+b²+c²) ≥ 3•³√(abc)×3•³√(a²b²c²) = 9abc