Expression : cosAcotA/(1 - sinA) = x
= $$\frac{cos A}{sin A} \times \frac{cos A}{1 - sin A}$$
Multiplying numerator and denominator by $$(1 + sin A)$$
= $$\frac{cos A}{sin A} \times \frac{cos A}{1 - sin A} \times \frac{(1 + sin A)}{(1 + sin A)}$$
= $$\frac{cos^2 A(1 + sin A)}{sin A(1 - sin^2 A)}$$
= $$\frac{cos^2 A(1 + sin A)}{sin A \times cos^2 A} = \frac{1 + sin A}{sin A}$$
= $$\frac{sin A}{sin A} + \frac{1}{sin A} = 1 + cosec A$$
=> Ans - (B)
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