Expression : 1/(tanA + cotA)
= $$1 \div (\frac{sinA}{cosA}+\frac{cosA}{sinA})$$
= $$1 \div (\frac{sin^2A+cos^2A}{sinAcosA})$$
= $$1 \times sinAcosA=sinAcosA$$
Multiplying and dividing by $$(sinAcosA)$$
= $$\frac{sin^2Acos^2A}{sinAcosA} = (\frac{cos^2A}{sinA} \times \frac{sin^2A}{cosA})$$
= $$(\frac{1-sin^2A}{sinA}) \times (\frac{1-cos^2A}{cosA})$$
= $$(\frac{1}{sinA}-sinA) \times (\frac{1}{cosA}-cosA)$$
= $$(cosecA-sinA)(secA-cosA)$$
=> Ans - (D)
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