化简:(x/(x-1)-2x/(x+1))÷x/(x2-1)

问题描述:

化简:(x/(x-1)-2x/(x+1))÷x/(x2-1)

原式=(x²+x-2x²+2x)/(x+1)(x-1)×(x+1)(x-1)/x
=(-x²+3x)/x
=-x+3