The value of the expression \( \Large 1 - \frac{\sin^{2} y}{1+\cos y}+\frac{1 + \cos y}{\sin y}-\frac{\sin y}{1- \cos y} \) is equal to;


A) 0

B) 1

C) \( \Large \sin y \)

D) \( \Large \cos y \)

Correct Answer:
D) \( \Large \cos y \)

Description for Correct answer:
The given expression can be written as

\( \Large \frac{1+\cos y - \sin^{2}y}{1+\cos y} + \frac{ \left(1-\cos^{2}y\right)-\sin^{2}y }{\sin y \left(1-\cos y\right) } \)

= \( \Large \frac{\cos y \left(1+\cos y\right) }{1+\cos y}+0= \cos y \)

Part of solved Trigonometric ratio questions and answers : >> Elementary Mathematics >> Trigonometric ratio








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