The value of $\lambda$ for which two vectors $2\hat{i}-\hat{j}+2\hat{k}$ and $3\hat{i}+\lambda\hat{j}+\hat{k}$ are perpendicular is
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 8 ##
Dot product of two mutually perpendicular vectors is zero.
$\Rightarrow 2 \times 3 + (-1)\lambda + 2 \times 1 = 0$
$\Rightarrow \lambda = 8$