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# Reduction Formula watch

1. Hey there, I've been struggling with this one for quite a while.

I need to show that:

I(n) = integral of ((e^sinx)(cosx)(sin^n x)) dx

comes down to I(n) = e - n I(n-1)

The integral doesn't have any limits, but I used the substitution y=sinx and then integrated by parts. I ended up with
I(n) = (y^n)(e^y) - n I(n-1)

Clearly, (y^n)(e^y) doesn't equal e, so I've made a mistake. Any help would be much appreciated. Thanks
2. (Original post by 4mar_ar5en4l)
...
It is a typo, what you have done is correct. The limits are probably meant to be (0, pi/2)
3. (Original post by Lord of the Flies)
It is a typo, what you have done is correct. The limits are probably meant to be (0, pi/2)
Oh thanks

Was starting to get a bit frustrated with that question.

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