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Topic: Difference in integral not understood
Replies: 4   Last Post: Sep 7, 2010 7:47 AM

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 Nikunj Parikh Posts: 3 From: India Registered: 9/6/10
Difference in integral not understood
Posted: Sep 6, 2010 12:49 AM
 Graphical representation.doc (47.0 K)

Hi

I am out of touch of maths for last 12 years and now reviving my math.
I am getting two different answers for the same integral.

I= Integral (sinx)^2(cosx)dx

method-1
If I proceed with (sinx)^2 = 1-(cosx)^2, I endup with answer sinx-((cosx)^4)/4)

method-2
with method of substitution u=sinx and hence du=cosxdx so the answer is ((sinx)^3)/3

Since both the methods look correct me, I am unable to find reason for this difference. Can some one help me

Date Subject Author
9/6/10 Nikunj Parikh
9/6/10 Federico Zanolla
9/7/10 Nikunj Parikh
9/7/10 Nikunj Parikh