Prove that: `sqrt((1-sintheta)/(1+sintheta))+sqrt((1+sintheta)/(1-sintheta))`=`2/(costheta)` and `-2/(costheta)`,if `0 <= theta < pi/2`,and if `pi/2 < theta <= pi`

Explanation

To prove the equation

\[ \sqrt{\frac{1 - \sin \theta}{1 + \sin \theta}} + \sqrt{\frac{1 + \sin \theta}{1 - \sin \theta}} = \frac{2}{\cos \theta} \quad \text{for } 0 \leq \theta < \frac{\pi}{2} \]

and

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