(1- tan x + sec x)/(1+tan x + sec x) = cos x/(1+sin x)

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- February 1st 2010, 08:30 AMsnigdhaProve the following trigonometrical identity-
(1- tan x + sec x)/(1+tan x + sec x) = cos x/(1+sin x)

- February 1st 2010, 11:19 AMHenryt999Hii
quick question, are you allowed to manipulate the right side of the equation? Some teachers donīt appreciate that..

What have you tried so far?

Have you tried writing

and

Doing so will easily give you a common denominator on the left side of the = sign... - February 1st 2010, 09:37 PMsnigdha
well i'm afraid i've never tried that....if u know some other method to get this done then plz try that out...(Speechless)

- February 1st 2010, 10:58 PMSoroban
Hello, snigdha!

If you know this identity: . , here's another approach.

Quote:

Prove: /

Multiply by .

. . . . . .

. . . . .

Multiply by

- February 1st 2010, 11:45 PMGrandad
- February 2nd 2010, 10:55 PMpacman
Soroban and Grandad did it again wih EASE, wow!

http://www1.wolframalpha.com/Calcula...image/gif&s=49

! - February 3rd 2010, 12:38 AMGrandad