If $\frac{{{a^2} + 1}}{{2a}} = \cos \,\,\theta $, then $\frac{{{a^6} + 1}}{{2{a^3}}} = $

JEE MATHEMATICS MCQ: MULTIPLE AND SUBMULTIPLE ANGLES

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Application +4 | -1

\frac{{{a^2} + 1}}{{2a}} = \cos \,\,\theta

, then

\frac{{{a^6} + 1}}{{2{a^3}}} =

View answer and explanation

Correct option: D

\cos \,\,3\theta

Option D (

\cos \,3\theta

) is correct because by manipulating the given equation and using trigonometric identities, we can find that

\frac{{a^6 + 1}}{{2{a^3}}} = \cos \,3\theta

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