This isn't a homework question, it's just for personal enrichment.(adsbygoogle = window.adsbygoogle || []).push({});

I've been trying to prove that [itex]\tan\frac{\theta}{2}=\frac{\sin\theta}{1+\cos\theta}[/itex]

I tried starting off with [tex]\tan\frac{\theta}{2}=\frac{\sin\frac{\theta}{2}}{\cos\frac{\theta}{2}}[/tex]

is this even the right way to start the proof? if so could someone point me the right way please? I'd really appreciate it.

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# Proof of a Trig Identity

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