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Vector Algebra question

2011 · Shift 2 · Q31

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PYQ Library
JEE Advanced
Mathematics
Vector Algebra
2011 · Shift 2 · Q31

Vector Algebra question

2011 · Shift 2 · Q31

JEE AdvancedMathematicsVector AlgebraNumerical+4 / −1

Let

\overrightarrow a = - \widehat i - \widehat k,\overrightarrow b = - \widehat i + \widehat j

and

\overrightarrow c = \widehat i + 2\widehat j + 3\widehat k

be three given vectors. If

\overrightarrow r

is a vector such that

\overrightarrow r \times \overrightarrow b = \overrightarrow c \times \overrightarrow b

and

\overrightarrow r .\overrightarrow a = 0,

then the value of

\overrightarrow r .\overrightarrow b

is

Numerical answer

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