Question

1.把（x-y）看做一个整体,化简1/4（x-y）+2（x-y)的平方-3/4（x-y）-5（x-y)的平方.

Answer 1

（x-y)/4+2(x-y)²-3(x-y)/4-5(x-y)²

=(1/4-3/4)(x-y)+(-3-5)(x-y)²

=-(x-y)/2-8(x-y)²