1. ## Integtration using u substitution help please

Hi all i am trying to integrate the following but can't see the wood for the trees..
[Cos(x/2)-sin(3x/2)]dx

So far i have u=(x/2) and du=1/2. This is where i am starting to lose my mind as i cannot seem to make this fit the standard integrals. Any help would be greatly appreciated

2. ## Re: Integtration using u substitution help please

Originally Posted by tommorgan
Hi all i am trying to integrate the following but can't see the wood for the trees..
[Cos(x/2)-sin(3x/2)]dx
$\int {(\cos (\theta ) - \sin (3\theta ))d\theta = \sin (\theta ) + \frac{1}{3}\cos (3\theta )}$

3. ## Re: Integtration using u substitution help please

You can do each term separately, each with a different substitution.