How do I find the integral intx^5*ln(x)dx ?

1 Answer
Sep 24, 2014

By Integration by Parts,

int x^5lnx dx=x^6/36(6lnx-1)+C

Let us look at some details.

Let u=lnx and dv=x^5dx.
Rightarrow du={dx}/x and v=x^6/6

By Integration by Parts

int udv=uv-int vdu,

we have

int (lnx)cdot x^5dx=(lnx)cdot x^6/6-int x^6/6cdot dx/x

by simplifying a bit,

=x^6/6lnx-int x^5/6dx

by Power Rule,

=x^6/6lnx-x^6/36+C

by factoring out x^6/36,

=x^6/36(6lnx-1)+C