Question

计算：x的平方+x-6/x-3/x+3/x的平方-6-x.x的平方+2xy+y的平方/xy-y的平方乘以x的平方-2xy

Answer 1

x的平方+x-6/x-3/x+3/x的平方-6-x

=(x+3)(x-2)/(x-3)×(x-3)(x+2)/(x+3)

=(x-2)(x+2)

=x²-4

x的平方+2xy+y的平方/xy-y的平方乘以x的平方-2xy+y的平方/xy+y的平方

=(x+y)²/y(x-y)×(x-y)²/y(x+y)

=(x+y)(x-y)/y²

=(x²-y²)/y²