Still confused with u substitution. Can someone show me how they would solve this by U substitution?

the integral from .5 to 1 of ln(2x+3) over 2x+3 dx.

u= ln(2x+3)

du=2/2x+3 dx

Where do i go from here? I was just puting the u on top so it would look like this... u/2x+3 but now i have a u and an x. What do I do?

Thanks.