Hi, today I was writing my Identities final test and got stuck on one question which I couldn't solve.(adsbygoogle = window.adsbygoogle || []).push({});

The question was: If [tex]sinB=-\frac{5}{13}[/tex] find the exact value of [tex]tan2B[/tex].

I've got this far, correct me if I went wrong anywhere: [tex]tan2B=\frac{sin2B}{cos2B}=\frac{2sinBcosB}{2cos^2B-1}[/tex]

Then, when I tryied to solve further I came to a dead end, even though I tried many different ways.

Thanx in advance!

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# Trig: Basic Identities Problem

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