Question

当a为何值时,x-2分之x-1-x+1分之x-2=(x-2)X(x+1)分之2x+a的解是负数.

Answer 1

(x-1)/(x-2)-(x-2)/(x+1)=(x-2)(2x+a)/(x+1)

同乘（x+1)(x-2)

(x-1)(x+1)-(x-2)^2=2x+a

2x-5=a

x=(a+5)/2