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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
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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
Read Proving trigonometric identities
Albert
1/20/09
Read Re: Proving trigonometric identities
Angus Rodgers
1/20/09
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Albert
1/20/09
Read Re: Proving trigonometric identities
Angus Rodgers
1/20/09
Read Re: Proving trigonometric identities
Albert
1/20/09
Read Re: Proving trigonometric identities
Angus Rodgers
1/20/09
Read Re: Proving trigonometric identities
Angus Rodgers
1/20/09
Read Re: Proving trigonometric identities
Guest
1/20/09
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Angus Rodgers
1/20/09
Read Re: Proving trigonometric identities
Albert
1/20/09
Read Re: Proving trigonometric identities
Angus Rodgers
1/20/09
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matt271829-news@yahoo.co.uk
1/21/09
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Albert
1/21/09
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adder
1/21/09
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matt271829-news@yahoo.co.uk
1/23/09
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Albert
1/23/09
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Angus Rodgers
1/23/09
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Angus Rodgers
1/23/09
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Passerby
1/23/09
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Dave Dodson
1/24/09
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Albert
1/24/09
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Angus Rodgers
1/24/09
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Albert
1/26/09
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Albert
1/26/09
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Driveby
1/26/09
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Albert
1/26/09
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A N Niel
1/27/09
Read Re: Proving trigonometric identities
Albert
1/20/09
Read Re: Proving trigonometric identities
adder
1/20/09
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victor_meldrew_666@yahoo.co.uk
1/20/09
Read Re: Proving trigonometric identities
Dave Dodson
1/20/09
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Pfsszxt@aol.com
1/20/09
Read Re: Proving trigonometric identities
Albert

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