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Vector Algebra question

2018 · 15 Apr · Shift 1 · Q38

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PYQ Library
JEE Main
Mathematics
Vector Algebra
2018 · 15 Apr · Shift 1 · Q38

Vector Algebra question

2018 · 15 Apr · Shift 1 · Q38

JEE MainMathematicsVector AlgebraMCQ+4 / −1

If

\overrightarrow a ,\,\,\overrightarrow b ,

and

\overrightarrow C

are unit vectors such that

\overrightarrow a + 2\overrightarrow b + 2\overrightarrow c = \overrightarrow 0 ,

then

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

is equal to :

A
${{\sqrt {15} } \over 4}$
B
${{1} \over {4}}$
C
${{15} \over {16}}$
D
${{\sqrt {15} } \over 16}$

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