I'm lost as to how to go about solving this. u = 4x and du = 4 dx but beyond that I'm stumped. That constant in the denominator confuses me.
Because if you have an integral of the form
you make the substitution .
This is so that you can factor out the and then make use of the identity .
And since the derivative of is , this also means that the will be eliminated (as you will end up with them on the top and bottom).