Question

计算(x^2-x-2/x^2-x-6)/(x^2+x-6/x^2+x-2)的值

Answer 1

答：这一题明显就是分解因式的题目,之后变成平方差.原式=（x^2-1）(x^2-4)/(x^2-9)(x^2-4)=x^2-1/(x^2-9)