Can someone please see if I did it right or not?
Substitute with
Do I have to add +C?
Thanks a lot
There is no need to actually do the integral- this is an exercise in using the "Fundamental Theorem of Calculus":
Here, because the upper limit is rather than x, you need to use the substitution . That way the upper limit is (assuming x is positive). Now and so that and the integral becomes
and, by the Fundamental Theorem of Mathematics, the derivative of that is
just by replacing u in the integrand by x.