Expression : (cos A + sin A)(cot A + tan A)
= $$(cosA+sinA)(\frac{cosA}{sinA}+\frac{sinA}{cosA})$$
= $$(cosA+sinA)(\frac{sin^2A+cos^2A}{sinAcosA})$$
= $$\frac{cosA+sinA}{sinAcosA}$$
= $$\frac{cosA}{sinAcosA}+\frac{sinA}{sinAcosA}$$
= $$\frac{1}{sinA}+\frac{1}{cosA}=cosecA+secA$$
=> Ans - (A)
Create a FREE account and get: