How do you integrate int x^2 ln 5x dx x2ln5xdx using integration by parts?

1 Answer
Feb 17, 2016

Start by letting u=ln(5x)u=ln(5x) and dv=x^2\ dx to ultimately get int \ x^2ln(5x)\ dx=1/3 x^3 ln(5x)-x^3/9+C.

Explanation:

If you let u=ln(5x) and dv=x^2\ dx, then du=1/(5x) * 5\ dx=1/x\ dx and v=x^3/3. Therefore

\int\ x^2ln(5x)\ dx=uv-\int\ v\ du

=1/3 x^3 ln(5x)-\int\ x^2/3\ dx=1/3 x^3 ln(5x)-x^3/9+C.