Question

计算：（x-y)分之x-（x+y）分之y+（x的平方-y的平方）分之（2xy）

Answer 1

=[x(x+y)-y(x-y)+2xy]/(x+y)(x-y)

=(x²+xy-xy+y²+2xy)/(x+y)(x-y)

=(x+y)²/(x+y)(x-y)

=(x+y)/(x-y)