(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

prove that: tan(1+cos(x))^2 = 1-cos(x)

2. Relevant equations

trig identities, like the pythagorean, sum/difference, double/half angle identities, power reducing identities, etc...

3. The attempt at a solution

i'm not sure where to start; i tried using the pythagorean identity where 1+tan(X)^2 = sec(x)^2, but couldn't get anywhere after that :\

then i used my calculator and made X a random number. i typed in the left side expression, and pressed enter. i then typed in the right hand expression, and pressed enter. the two values were different. what did i do wrong?

i'm not really sure anymore that its even possible to prove the above...

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# Homework Help: Precalculus: proving trigonometric identity

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