trig identity problem: (sinx + tanx) / (1 + cosx) = tanx

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sully039
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trig identity problem: (sinx + tanx) / (1 + cosx) = tanx

Postby sully039 » Sun Sep 04, 2011 8:38 pm

(sinx+tanx)/(1+cosx)=tanx

So far I have,
L.S
(sinx+sinx/cosx)/(1+cosx)
[(sinxcosx+sinx)/(cosx)]/(1+cosx)
(sinxcosx+sinx)/(cosx) * 1/(1+cosx)
(sinxcosx+sinx)/(cosx+cos^2x)
...and now I'm stuck.

Could someone help me solve this and point out what I did wrong?
Thanks

nona.m.nona
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Joined: Sun Dec 14, 2008 11:07 pm
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Re: trig identity problem: (sinx + tanx) / (1 + cosx) = tanx

Postby nona.m.nona » Mon Sep 05, 2011 3:04 pm

sully039 wrote:[(sinxcosx+sinx)/(cosx)]/(1+cosx)
(sinxcosx+sinx)/(cosx) * 1/(1+cosx)

Factor the numerator "sin(x)cos(x) + sin(x)". Do the cancelation. Proceed from that point.


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