(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

(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. Relevant 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.

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# What did i do wrong in my integration?

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