- #1

Geronimo85

- 20

- 0

Integral[(e^ax)cos^2(2bx)dx] where a and b are positive constants

So far all I've got is:

(e^ax)cos^2(2bx)= (e^ax)*[(e^(i*2*b*x) - e^(-i*2*b*x))/2]^2

because: cosx = (e^ix - e^-ix)/2

squaring inside the brackets gets me:

(e^ax)* [((e^(i*2*b*x)-e^(-i*2*b*x)/2)^2]

I'm just really not getting something here