MCQ
If $a = 3i - j + 2k,$ $b = 2i + j - k,$ then $a \times (a\,.\,b) = $
  • A
    $3a$
  • B
    $3\sqrt {14} $
  • C
    $0$
  • None of these

Answer

Correct option: D.
None of these
d
(d) $a \times (a\,.\,b)$ is not meaningful.

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