Sorry but i dont know how to use latex yet or to add mathematical symbols somehow.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Prove that 1-sin2θ/cos2θ = 1-tanθ/1+tanθ

2. Relevant equations

sin2θ = 2tanθ/1+tan^{2}θ and cos2θ =1-tan^{2}θ/1+tan^{2}θ

I have allready proved from a previous exercise those two above so i pressume they may be useful.

3. The attempt at a solution

1-sin2θ/cos2θ = 1-2tanθ/1+tan^{2}θ/1-tan^{2}θ/1+tan^{2}θ=

i then multiply the fraction with (1+tan2θ) and i am left with

1-2tanθ/1-tan^{2}θ

i have tried various things but i suppose this is the way to go.. maybe not, i dont know, i am stuck. Can someone help me on that one please?

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# Homework Help: Trigonometry equatation

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