If a ,. ,i = 4, then (a j) ,. ,(2j - 3k) = - Vidyadip

MCQ

If $a\,.\,i = 4,$ then $(a \times j)\,.\,(2j - 3k) = $

A
$12$
B
$2$
C
$0$
✓
$-12$

✓

Answer

Correct option: D.

$-12$

d
(d) $(a \times j)\,.\,(2j - 3k) = a\,.\{ j \times (2j - 3k)\} $

$ = a\,.\,\{ - 3(j \times k)\} = - 3(a\,.\,i) = - 12.$

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