Question

计算：（1/a-1-1)÷a²-1/a+2;解方程1/x-2=3/2x+1.

Answer 1

1、原式=(1-a+1)/(a-1)×(a+2)/(a+1)(a-1)

=(2-a)/(a-1)×(a+2)/(a+1)(a-1)

=(2-a)(a+2)/(a-1)²(a+1)

2、两边乘以(x-2)(2x+1)得

3x-6=2x+1

∴x=7

检验：x=7是方程的解