Prove the following identities: `(1-sintheta)/(1+sintheta)=` `(sectheta-tantheta)^2`

Explanation

To prove the identity

\[ \frac{1 - \sin \theta}{1 + \sin \theta} = (\sec \theta - \tan \theta)^2 \]

we will start with the left-hand side (LHS) and manipulate it to show that it equals the right-hand side (RHS).

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