(a ,. ,i) ,i + (a ,. ,j)j + (a ,. ,k) ,k = - Vidyadip

MCQ

$(a\,.\,i)\,i + (a\,.\,j)j + (a\,.\,k)\,k = $

✓
$a$
B
$2a$
C
$0$
D
None of these

✓

Answer

Correct option: A.

$a$

a
(a) Let $a = xi + yj + zk$. Then $(a.i)i + (a.j)j + (a.k)k = a.$

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