Use of De-Moivre's theorem........

Can anyone plz explain the use of complex numbers ( de-moivre's theorem) in finding out the integral of type

âˆ«sinmxcosnxdx , where both m,n are positive integers.

2 Answers

481

Anurag Ghosh ·2013-08-02 19:00:10

m and n are in the powers

2305

Shaswata Roy ·2013-08-03 09:05:56

Use:

âˆ«sin(mx)cos(nx)dx
=âˆ«(e^mx-e^mx) (e^nx+e^nx)2idx

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