已知:a+b=1,a^2+b^2=2,求(a^8-b^8)^2的值

问题描述:

已知:a+b=1,a^2+b^2=2,求(a^8-b^8)^2的值

(a^8-b^8)^2 =[(a^4+b^4)(a^4-b^4)]^2 =[(a^4+b^4)(a^2+b^2)(a^2-b^2)]^2 =[(a^4+b^4)(a^2+b^2)(a+b)(a-b)]^2 =[(a^4+b^4)(2)(1)(a-b)]^2 =4(a-b)^2(a^4+b^4)^2 ∵a+b=1,(a+b)^2=1...