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Vector Algebra question

2021 · 25 Jul · Shift 2 · Q34

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JEE Main
Mathematics
Vector Algebra
2021 · 25 Jul · Shift 2 · Q34

Vector Algebra question

2021 · 25 Jul · Shift 2 · Q34

JEE MainMathematicsVector AlgebraMCQ+4 / −1

If

\left| {\overrightarrow a } \right| = 2,\left| {\overrightarrow b } \right| = 5

and

\left| {\overrightarrow a \times \overrightarrow b } \right|

= 8, then

\left| {\overrightarrow a .\,\overrightarrow b } \right|

is equal to :

A
6
B
4
C
3
D
5

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