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