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

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

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

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

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)*

Se Zoti vete e tha me goje,se kombet shuhen permbi dhe,por SHqiperia do te roje,per te,per te luftojme ne.

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