Question

Write the direction cosines of the vector $\hat{i}+2\hat{j}+3\hat{k}$.

Answer 1

Given: $\hat{i}+2\hat{j}+3\hat{k}$
Then, direction cosines are
$\frac{1}{\sqrt{1^2+2^2+3^2}},\frac{2}{\sqrt{1^2+2^2+3^2}},\frac{3}{\sqrt{1^2+2^2+3^2}}$ or, $\frac{1}{\sqrt{14}},\frac{2}{\sqrt{14}},\frac{3}{\sqrt{14}}$.