25x的二次方-10x(x-y)+(x-y)的2次方
问题描述:
25x的二次方-10x(x-y)+(x-y)的2次方
答
25x^2-10x(x-y)+(x-y)^2
=[5x-(x-y)]^2
=(5x-x+y)^2
=(4x+y)^2