If $1 + \cos \,\,x = k$, where $x$ is acute, then $\sin \,\,\frac{x}{2}$ is

JEE MATHEMATICS MCQ: MULTIPLE AND SUBMULTIPLE ANGLES

1 Easy

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Application +4 | -1

1 + \cos \,\,x = k

, where

x

is acute, then

\sin \,\,\frac{x}{2}

View answer and explanation

Correct option: D

\sqrt {\frac{{2 - k}}{2}}

Option D (

\sqrt {\frac{{2 - k}}{2}}

) is correct because by using the half-angle formula for sine and the given equation, we can derive this expression.

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