计算:(a²-4/a²-4a+4-2/a-2)÷a²+2a/a-2;(x²-1/x²-2x+1+1-x/x+1)÷x/x-1.
问题描述:
计算:(a²-4/a²-4a+4-2/a-2)÷a²+2a/a-2;(x²-1/x²-2x+1+1-x/x+1)÷x/x-1.
答
1、原式=[(a+2)/(a-2)-2/(a-2)]÷(a²+2a)/(a-2)=a/(a-2)*(a-2)/(a²+2a)=1/(a+2)
2、原式=[(x+1)/(x-1)+(1-x)/(x+1)]÷x/(x-1)=4x/(x^2-1)÷x/(x-1)=4/(x+1)