JEE MATHEMATICS MCQ: SEQUENCE OF SERIES

1 Easy

1 of 1

Application +4 | -1

\sin \beta

is geometric mean between

\sin \alpha

and

\cos \alpha

, then

\cos 2 \beta

is equal to

View answer and explanation

Correct option: A

2 \sin ^2\left(\frac{\pi}{4}-\alpha\right)

Option A (

2 \sin ^2(\frac{\pi}{4}-\alpha)

) is correct because by using the geometric mean property and trigonometric identities,

\cos 2 \beta

can be expressed in the given form.

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