Tip – If f1(x) and f2(x) are two functions , then an integral of the form ∫ f1 (x) f2 (x) dx can be INTEGRATED BY PARTS as
where f1(x) and f2(x) are the first and second functions respectively.
Taking f1(x) = cot-1x and f2(x) = x2,
where c is the integrating constant.
