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3D Geometry question

2022 · 26 Jun · Shift 2 · Q35

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PYQ Library
JEE Main
Mathematics
3D Geometry
2022 · 26 Jun · Shift 2 · Q35

3D Geometry question

2022 · 26 Jun · Shift 2 · Q35

JEE MainMathematics3D GeometryMCQ+4 / −1

Let

\overrightarrow a = \widehat i + \widehat j + 2\widehat k

,

\overrightarrow b = 2\widehat i - 3\widehat j + \widehat k

and

\overrightarrow c = \widehat i - \widehat j + \widehat k

be three given vectors. Let

\overrightarrow v

be a vector in the plane of

\overrightarrow a

and

\overrightarrow b

whose projection on

\overrightarrow c

is

{2 \over {\sqrt 3 }}

. If

\overrightarrow v \,.\,\widehat j = 7

, then

\overrightarrow v \,.\,\left( {\widehat i + \widehat k} \right)

is equal to :

A
6
B
7
C
8
D
9

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