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

Prove that sec^(2)(x/2) divided by 1 - tan^(2)(x/2) is sec x

2. Relevant equations

Trig identities.

3. The attempt at a solution

I used the identity: 1 + tan^2(x) = sec^2(x)

I get for numerator: 1 + tan^2(x/2)

I kept denominator same: 1 - tan^2(x/2)

I get the impression (intuition?) that this can be solved in its current form. But then since i couldn't after a while, i just went on to expand tan^2(x/2) using the double angle formula to get expressions in terms of tan(x). It turned into something lengthy, so i doubt that i'm doing it right.

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# Prove trigonometric expression

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