The value of for which the vectors 2 i + j - k and 2j + k are per… - Vidyadip

MCQ

The value of $\lambda $ for which the vectors $2\lambda i + j - k$ and $2j + k$ are perpendicular, is

✓
None
B
$-1$
C
$1$
D
Any value

✓

Answer

Correct option: A.

None

a
(a) Since $(2\lambda i + j - k)\,.\,(2j + k) = 1$ for every $\lambda ,$ therefore the vectors will not be perpendicular for any $\lambda .$

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