Question

先化简再求值x²-x/（x+1）×x²-1/（x²-2x+1）

Answer 1

x²-3x+2=(x-1)(x-2)=0

x=1,x=2

x=1,分母x²-2x+1=0,舍去

所以x=2

原式=[x(x-1)/(x+1)][(x+1)(x-1)/(x-1)²]

=x(x-1)(x+1)(x-1)/[(x+1)(x-1)²]

=x

=2