The value of \( \Large \frac{1}{1+\cos A}+\frac{1}{1-\cos A} \)
Correct Answer: A) \( \Large 2\cosh^{2}A \) |
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Description for Correct answer:
\( \Large \frac{1}{1+\cos A}+\frac{1}{1-\cos A} = \frac{1-\cos A+1+\cos A}{ \left(1+\cos A\right) \left(1-\cos A\right) } \)
=\( \Large \frac{2}{1-\cos^{2}A}=\frac{2}{\sin^{2}A}=2\cosh^{2}A \)
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