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**1. Homework Statement**

(dont know how to make the integral sign so bare with me please)

i will use | to signify the integral sign:

here is my problem:

|(sinx)(cos)dx

**2. Homework Equations**

n/a

**3. The Attempt at a Solution**

ok this is what i did:

first i changed it to (1/2)sin2x because sin2x=2sinxcosx

so now i have:

|(1/2)sin2xdx

then i said u = 2x and du=2dx

so now i have:

|(1/4)sinudu

which is:

(1/4)(-cos u) + C

which is:

(1/4)(-cos2x) + C

where is my error?

also, can someone give me a brief overview of the best strategy to figure out what type of integration to use? what do you look for to know when to use trig substituion, integration by parts, u-substitution, etc...

ie, how do you know? thanks.