Question

(x+1分之1-x-1分之1)÷x²-1分之2

Answer 1

(1/(x+1)-1/(x-1))/x²-1分之2
=(x-1-x-1)/(x^2-1)/x²-1分之2
=-2/(x^2-1)/x²-1分之2
=-1

Answer 2

[1/(x+1)-1/(x-1)] × (x+1)(x-1)/2
=1/(x+1)× (x+1)(x-1)/2 -1/(x-1)× (x+1)(x-1)/2
=(x-1)/2-(x+1)/2
=-1

追问

让我算算

追答

好的，利用乘法分配律
括号内通分也可

请采纳