Evaluate the integral $$\int {\frac{3}{(x+a)(x+b)}}\, dx$$ for the cases where $a=b$ and where $a \ne b.$

Note: For the case where $a=b,$ use only $a$ in your answer. Also, use an upper-case "C" for the constant of integration.

If $a=b:$

If $a \ne b:$