分式计算 1-x/x²+x-2÷x²-1/x+2
问题描述:
分式计算 1-x/x²+x-2÷x²-1/x+2
答
(1-x)/(x²+x-2)÷[(x²-1)/(x+2)]
=-(x-1)/[(x-1)(x+2)]÷[(x-1)(x+1)/(x+2)]
=-1/(x+2)×(x+2)/[(x-1)(x+1)]
=1/(1-x²)