# Integration by substitution

1. Mar 8, 2009

1. The problem statement, all variables and given/known data
Use substitution to evaluate the integral.
$$\int \frac{4cos(t)}{(2+sin(t))^2}dt$$

2. Relevant equations
None, really.

3. The attempt at a solution
I'm not sure what to use as u, for the substitution. I've tried $$(2+sin(t))^2$$, as well as other attempts, but I can't seem to find anything.

2. Mar 8, 2009

Sorry, I meant
$$\int \frac{4cos(t)}{(2+sin(t))^2}dt$$

3. Mar 8, 2009

### gabbagabbahey

Why not try u=2+sin(t) ?

4. Mar 9, 2009

### Staff: Mentor

Always try a simple substitution before you try the more complicated substitutions. If your simple substitution doesn't work, you won't have wasted much time.