How do you integrate (3x)7(3x)2dx?

1 Answer
Dec 21, 2016

(3x)7(3x)2dx=7(3x)22ln7+C

Explanation:

Substitute t=(3x)2, dt=2(3x)dx, and consider that 7α=eαln7:

(3x)7(3x)2dx=12eln7tdt=12ln7eln7t+C=7(3x)22ln7+C