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Topic: Proving trigonometric identities
Replies: 32   Last Post: Jan 27, 2009 1:59 AM

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 victor_meldrew_666@yahoo.co.uk Posts: 725 Registered: 5/19/06
Re: Proving trigonometric identities
Posted: Jan 20, 2009 6:36 AM

On 20 Jan, 07:19, Albert <albert.xtheunkno...@gmail.com> wrote:
> Hey everybody!!! how do you prove that:
>
> cos(x) / [1 - sin(x)] = [1 + sin(x)] / cos(x)

To prove any trigonometric identity in one variable x,
write cos(x) = (z + 1/z)/2 and sin(x) = (z - 1/z)/(2i)
on both sides and check that you have an identity of
rational functions of z.

> Could sum1 plz give me a suggestion?

You could learn to spell?

Date Subject Author
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 Angus Rodgers
1/20/09 Guest
1/20/09 Angus Rodgers
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 matt271829-news@yahoo.co.uk
1/21/09 Albert
1/21/09 matt271829-news@yahoo.co.uk
1/23/09 Albert
1/23/09 Angus Rodgers
1/23/09 Angus Rodgers
1/23/09 Passerby
1/23/09 Dave Dodson
1/24/09 Albert
1/24/09 Angus Rodgers
1/24/09 Albert
1/26/09 Albert
1/26/09 Driveby
1/26/09 Albert
1/26/09 A N Niel
1/27/09 Albert