MCQ
The vector $2\,i + j - k$ is perpendicular to $i - 4j + \lambda k,$ if $\lambda = $
- A$0$
- B$-1$
- ✓$-2$
- D$-3$
✓
Answer
Correct option: C.
$-2$
c
(c) $a.b = (2 - 4 - \lambda ) = 0 \Rightarrow \lambda = - 2.$
(c) $a.b = (2 - 4 - \lambda ) = 0 \Rightarrow \lambda = - 2.$
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