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Can anyone help me verify the following trig identity:

$$(1-\cos A)(1+\sec A)(\cot A)= \sin A.$$

My work so far is

$$(1-\cos A)\left(1+\frac{1}{\cos A}\right)\frac{\cos A}{\sin A}=\sin A$$

But I am stuck around this part.

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    You should have $\sec A = 1/\cos A$. If you make this correction, you should be able to get your equation to $1 - \cos^2 A = \sin^2 A$, which is a known identity ($\cos^2 A + \sin^2 A = 1$).2012-07-14
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    yes I meant sec=1/cos I just wrote my work part wrong.2012-07-14

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