问题描述： 第十一题,答案已给出. 1个回答 分类：数学 2014-11-24 问题解答： 我来补答 解11题原式=[ (x-y)^4 -(x^4 -y^4) ]÷[ (x+y)(x-y) ]²=[ (x-y)^4 -(x²+y²)(x+y)(x-y) ]÷[ (x+y)²(x-y)² ]=(x-y)^4 ÷ [ (x+y)²(x-y)² ] -(x²+y²)(x+y)(x-y)÷[ (x+y)²(x-y)² ]=(x-y)²/(x+y)² - (x²+y²)/[ (x+y)(x-y) ]=(x-y)²/(x+y)² - (x²+y²)/(x²-y²)正确答案应该选 C 展开全文阅读
