If a = 3i - j + 2k, b = 2i + j - k, then a (a ,. ,b) = - Vidyadip

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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