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    evaluate the integral of coshx sinh^2 dx limits are a=0,b=1
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    Notice that coshx is the derivative of sinhx so you have:
    f'(x) * f(x)^2

    What's the integral of something of this form?
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    can u write the full answer plz!
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    (Original post by f40spider)
    can u write the full answer plz!
    Try differentiating  \sinh ^3 x by the chain rule.
    You should get something that looks similar to what you're trying to integrate. You can make it exact by multiplying by a constant (constants do not affect differentiation/integration).
    For the purposes of this you can think of integration as reverse differentiation, for example if you differentiate x^2 you get 2x and if you integrate 2x you get x^2.

    This is how I always do these problems, it also works if you have to integrate something like  \sin x \cos ^n x , if you differentiate  \cos ^{n+1} x you'll get something in a similar form.
 
 
 
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Updated: January 27, 2010

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