Verify trig identity: 1/(tanx-secx) + 1/(tanx+secx) = -2tanx

HannahBanana4011

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I've completed about 12 similar homework problems, but for some reason, I can't figure out how to verify this one. Any help would be greatly appreciated!!

[1/(tanx-secx)]+[1/(tanx+secx)] = -2tanx
 
Re: Verifying trig identites

Cross multiply as you would when adding any fraction, then simplify.

\(\displaystyle \frac{1}{tan(x)-sec(x)}+\frac{1}{tan(x)+sec(x)}\)

=\(\displaystyle \frac{tan(x)+sec(x)+tan(x)-sec(x)}{tan^{2}(x)-sec^{2}(x)}\)

Now, simplify. See it?. Remember the identity \(\displaystyle tan^{2}(x)-sec^{2}(x)=-1\)
 
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