math
posted by mathstudent .
integrate: (x^2 + 1)^k dx

There is a reduction formula for this. The number of terms in the answer depends upon the number k.
The integral is
{1/[2(2k+1)]}*[2x*(x^2+1)^k + 4k S (x^2+1)^(k1) dx]
Where S represents an integral sign.