Integration with Sines and Cosines

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Ayesh
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Homework Statement



[tex]\int[/tex]sinxcosx/sin^4x+cos^4x


Homework Equations



sin^2x=1/2-1/2cos(2x)

cos^2x=1/2+1/2cos(2x)

sinxcosx=1/2sin(2x)

The Attempt at a Solution



[tex]\int[/tex]1/2 sin(2x)/(1/2-1/2cos(2x))^2 + (1/2 + 1/2cos(2x))^2

[tex]\int[/tex]1/2 sin(2x)/1/2 + 1/2cos^2(2x)

...?

Am I on the right track?
 
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Hi Ayesh! :smile:

(have an integral: ∫ and try using the X2 tag just above the Reply box :wink:)

Ayesh said:
… [tex]\int[/tex]1/2 sin(2x)/1/2 + 1/2cos^2(2x)

...?

Am I on the right track?

Yes, that's fine.

(though it would have been quicker to notice that the original denominator is almost the square of cos2x + sin2x :wink:)

And you should be able to integrate it immediately. :smile: