MCQ
If $a = 2i + 4j + 2k$ and $b = 8i - 3j + \lambda k$ and $a\, \bot \,b,$ then value of $\lambda $ will be
  • A
    $2$
  • B
    $-1$
  • $-2$
  • D
    $1$

Answer

Correct option: C.
$-2$
c
(c)  Clearly, $8 \times 2 - 3 \times 4 + 2 \times \lambda = 0 \Rightarrow \lambda = - 2.$

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