Simple Calculus (indefinite integral)

AryRezvani
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Homework Statement



Find the indefinite integral:
∫ Cos32x Sin22x dx

Homework Equations



None required

The Attempt at a Solution



Lost on where to start. If someone could just start me off.
 
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either use the identity
cos3(2x)sin2(2x)=(1/16) (2 cos(2 x)-cos(6 x)-cos(10 x))
or
cos3(2x)sin2(2x)=(1/2)(sin2(2 x)-sin4(2 x))(sin(2x))'
and the substitution u=sin(2x)
 
AryRezvani said:

Homework Statement



Find the indefinite integral:
∫ Cos32x Sin22x dx

Homework Equations



None required

The Attempt at a Solution



Lost on where to start. If someone could just start me off.
Write cos3(2x) as cos(2x) cos2(2x)

Then use the identity,
cos2(2x)=1-sin2(2x)​
After that, a simple substitution should work fine.
 
SammyS said:
Write cos3(2x) as cos(2x) cos2(2x)

Then use the identity,
cos2(2x)=1-sin2(2x)​
After that, a simple substitution should work fine.

Knocked it out, thanks guys.
 
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