More Integration by Substitution (1 Viewer)

Crosswinds

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Could someone please show me why the answer to this:

∫ (sinx)/(√(1 + 2cosx)) dx {with limits pi/2 and 0} using the substitution y = 1 + 2cosx

is

√3 - 1?

I keep getting a quarter of this answer??

Thanks! (Sorry I don't know how to make my limits pretty)
 

Cazic

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Letting y = 1 + 2cos(x) we have -dy/2 = sin(x) dx and:



So




Edit: I must have missed a minus sign somewhere if your answer is correct /shrug
Edit2: Found it :)
 
Last edited:

jet

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Don't forget the dy in the second integrand ;)
 

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