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

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 Albert Posts: 282 Registered: 12/9/07
Proving trigonometric identities
Posted: Jan 20, 2009 2:19 AM

Hey everybody!!! how do you prove that:

cos(x) / [1 - sin(x)] = [1 + sin(x)] / cos(x)
?

Currently, I don't think cosec(theta) = 1 / sin(theta),
sec(theta) = 1 / cos(theta) are necessary in this proof.
I've fiddled around with sec(theta) = 1 / cos(theta) and cot(theta) =
1 / tan(theta) but I can't get it turn in2 the right hand side.
I've had two complete proofs and I've done one proof all by myself but
they all involved the square relations and now the fourth and final
problem in the mini-section gives me an equation without the squares :
( (and I don't know what 2do).

Could sum1 plz give me a suggestion?

TIA
Albert

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