integration Watch

dhokes
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#1
Report Thread starter 12 years ago
#1
:confused: Can someone show me how to do the following integration please:

∫e^x cosh x dx

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Jonny W
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#2
Report 12 years ago
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Integrate by parts.
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The Orientalist
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#3
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Just use integration by parts where: f(x)=e^x and g'(x)=cosh x and thus g(x)=sinh x
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dvs
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#4
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Or:
e^x cosh(x) = e^x (e^(x) + e^(-x))/2
= (e^(2x) + 1)/2

Which integrates to:
(0.5e^(2x) + x)/2 + C
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Jonny W
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#5
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Integrating by parts doesn't work (although I suggested it above!). Use

e^x cosh(x) = (1/2)(e^(2x) + 1)
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gyrase
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(Original post by Retropmot)
you can't get the integral by parts but when u do it

I = int(e cosh x)

I = e sinh x - int(e sinh x)

I = e sinh x - e cosh x + I

0 = e(sinh x - cosh x) = -1

Which step isn't valid?
You forgot the constant of integration.
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dhokes
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#7
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