Answer
$\frac{-n+3}{n(n-1)}$
Work Step by Step
By inspection, we see that the LCM of the denominators is $n(n-1)$. Therefore, we create a common denominator using this LCM and obtain:
$\frac{2}{n-1}-\frac{3}{n}$
=$\frac{n(2)-3(n-1)}{n(n-1)}$
=$\frac{2n-3n+3}{n(n-1)}$
=$\frac{-n+3}{n(n-1)}$
