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