计算 1.[(a+b)^2-(a+b)(a-b)]÷(-b) 2.[(x+y)(2x+y)+(x+y)(x-y)]÷3x

问题描述:

计算 1.[(a+b)^2-(a+b)(a-b)]÷(-b) 2.[(x+y)(2x+y)+(x+y)(x-y)]÷3x