Question:medium
$\vec{a} = \frac{1}{7}(2\hat{i} + 3\hat{j} + 6\hat{k})$, $\vec{b} = \frac{1}{7}(3\hat{i} - 2\hat{j} + \lambda \hat{k})$. If $\vec{a}$ and $\vec{b}$ are mutually perpendicular, then value of $\lambda$ is
$\vec{a} = \frac{1}{7}(2\hat{i} + 3\hat{j} + 6\hat{k})$, $\vec{b} = \frac{1}{7}(3\hat{i} - 2\hat{j} + \lambda \hat{k})$. If $\vec{a}$ and $\vec{b}$ are mutually perpendicular, then value of $\lambda$ is
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$\vec{a} \cdot \vec{b} = 0$ for perpendicular vectors.
Updated On: Apr 8, 2026
- $2$
- $-1$
- $6$
- $-6$
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The Correct Option is D
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