MCQ
The direction cosine of vector $\hat{i}-2 \hat{j}+3 \hat{k}$ is __________ .
  • A
    $\frac{1}{14}, \frac{2}{14}, \frac{3}{14}$
  • B
    $\frac{-1}{\sqrt{14}}, \frac{-2}{\sqrt{14}}, \frac{-3}{\sqrt{14}}$
  • $\frac{1}{\sqrt{14}}, \frac{-2}{\sqrt{14}}, \frac{3}{\sqrt{14}}$
  • D
    $1,-2,3$

Answer

Correct option: C.
$\frac{1}{\sqrt{14}}, \frac{-2}{\sqrt{14}}, \frac{3}{\sqrt{14}}$
C

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