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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