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Vector Algebra question

2024 · 4 Apr · Shift 2 · Q40

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JEE Main
Mathematics
Vector Algebra
2024 · 4 Apr · Shift 2 · Q40

Vector Algebra question

2024 · 4 Apr · Shift 2 · Q40

JEE MainMathematicsVector AlgebraMCQ+4 / −1

For

\lambda\gt 0

, let

\theta

be the angle between the vectors

\vec{a}=\hat{i}+\lambda \hat{j}-3 \hat{k}

and

\vec{b}=3 \hat{i}-\hat{j}+2 \hat{k}

. If the vectors

\vec{a}+\vec{b}

and

\vec{a}-\vec{b}

are mutually perpendicular, then the value of (14 cos

\theta)^2

is equal to

A
25
B
50
C
20
D
40

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