$\sqrt{\frac{1 + \cos \theta}{1 - \cos \theta}} + \sqrt{\frac{1 - \cos \theta}{1 + \cos \theta}}$ = ________.
Answer & explanation
Correct answer: option 3
$\sqrt{\frac{1 + \cos \theta}{1 - \cos \theta}} + \sqrt{\frac{1 - \cos \theta}{1 + \cos \theta}}$
= $\sqrt{\frac{(1 + \cos \theta)(1 - \cos \theta)}{(1 - \cos \theta)(1 - \cos \theta)}} + \sqrt{\frac{(1 - \cos \theta)(1 + \cos \theta)}{(1 + \cos \theta)(1 + \cos \theta)}}$
= \(\frac{1 - cos θ}{sinθ}\) + \(\frac{1 + cos θ}{sinθ}\)
= \(\frac{2}{sinθ}\) = 2cosecθ