#How do i solve this integral?

25 messages · Page 1 of 1 (latest)

wet wolf
arctic pelicanBOT
delicate veldt
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this looks interesting

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ok try using the identity $\cos(2x)=\cos^{2}(x)-\sin^{2}(x)$

vocal summitBOT
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chudcel

foggy axle
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Id use sin^2 (x)=(1-cos(2x))/2

wet wolf
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so then its 1/4 integral os cos2x-cos^2(2x)

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then use cos^2x = 1/2(1+cos2x)?

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it should be a sin4x/8

glass kindle
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for the first one with the cos2x, that +sin4x should be a -sin4x

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your answer for the second integral looks way too complicated

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i got a very simple answer

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wait, what is all those fractions at the very bottom?

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i used a different method for the second one, and got $\left(\frac{\cos4x}{32}-\frac{\cos2x}{8}\right)$

vocal summitBOT
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Helcovich Emire

glass kindle
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but i checked it, and both are correct - they differ by a constant

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though i think we need a +C at the end

wet wolf
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We had to use the parameter method

glass kindle
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what is the parameter method

wet wolf
wet wolf
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,solved

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.solved