MCQ
Three vectors $\overrightarrow a ,\,\overrightarrow b $and $\overrightarrow c $ satisfy the relation $\overrightarrow a \,.\,\overrightarrow b = 0$ and $\overrightarrow a \,.\,\overrightarrow c = 0.$ The vector $\overrightarrow a $ is parallel to
  • A
    $\overrightarrow b $
  • B
    $\overrightarrow c $
  • C
    $\overrightarrow b \,.\,\overrightarrow c $
  • $\overrightarrow b \times \overrightarrow c $

Answer

Correct option: D.
$\overrightarrow b \times \overrightarrow c $
d
(d ) $\vec a\,.\,\vec b = 0$ i.e. $\vec a $ and $\vec b$ will be perpendicular to each other

$\vec a\,.\,\vec c = 0$ i.e. $\vec a$ and $\vec c$ will be perpendicular to each other

$\vec b \times \vec c$ will be a vector perpendicular to both $\vec b$ and $\vec c$

So $\vec a$ is parallel to $\vec b \times \vec c$

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