Let a, b, c be three mutually perpendicular... | Vectors | JEE Main 2021

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JEE MAIN 2021

20-07-2021 S1

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Let $\vec{a}, \vec{b}, \vec{c}$-be three mutually perpendicular vectors of the same magnitude and equally inclined at an angle $\theta$, with the vector $\vec{a}+\vec{b}+\vec{c}$. Then $36 \cos ^2 2 \theta$ is equal to $\_\_\_\_$ .

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