JEE MATHEMATICS MCQ: DOT PRODUCT OF VECTORS

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\vec a,\;\,\vec b,\;\,\vec c

are three mutually perpendicular vectors of equal magnitude, then the angle

\theta

which

\vec a + \vec b + \vec c

makes with any one of three given vectors is given by

View answer and explanation

Correct option: A

{\cos ^{ - 1}}\,\,\frac{1}{{\sqrt 3 }}

Option A (

{\cos ^{ - 1}}\frac{1}{{\sqrt 3 }}

) is correct because it is derived by finding the cosine of the angle between the vector sum and one of the mutually perpendicular vectors.

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O A

O B

30^{\circ}

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