If a = 2i + 4j + 2k and b = 8i - 3j + k and a , ,b, then value of… - Vidyadip

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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