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#1 2010-10-17 03:00:20

123ronnie321
Member
Registered: 2010-09-28
Posts: 128

Trigonometry

sin(a) + sin(a+b) + sin(a+2b) +.....+ sin (a+nb) = ???

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#2 2010-10-17 03:56:29

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Trigonometry

Hi 123ronnie321;

This is provided that n = 0,1,2,3,4,...

There is a formula for that particular sum. I used a computer instead.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2010-10-17 03:56:56

G_Einstein
Member
Registered: 2008-08-30
Posts: 124

Re: Trigonometry


sorry didn;t had time to write it correctly but I think that the result is correct  notice that cosa=cos(a)   ans sinna=sin(na)  but I had not time to wrote it .....

Last edited by G_Einstein (2010-10-17 03:58:24)


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