Question

(1/1+cos A )+(1/1-cos A) = 2 cosec^2 A

Answer 1

$\frac{1}{1+cos A} + \frac{1}{1-cos A}$
$=\frac{1-cos A + 1+cos A}{1-cos ^{2} A} = \frac{2}{sin^{2} A} = 2cosec^{2} A$

Answer 2

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