Question

How would you compute the indefinite integral of 8cos(3x)sin(x) using complex exponentials?

Answer 1

\[
\cos(3 x)= \frac {e^{3ix}+e^{-3ix}}{2}\\
\sin (x) = \frac {e^{ix}-e^{-ix}}{2i}\\
\]

Answer 2

Now multiply out and integrate

Answer 3

Oh okay! So you just have to substitute those in, got it thanks.

Answer 4

Yes