Question

Find direction cosines of a vector $\overrightarrow{u}=(2,3,6)$ respectively.

• A. $0.33,0.65,0.78$
• B. $0.43,0.59,0.85$
• C. $0.28,0.42,0.85$
• D. $0.34,0.46,0.64$

Answer 1

Answer: (C)

$0.28,0.42,0.85$

$\overrightarrow{u}=(2,3,6)$
The direction cosines of the vector are

$(\frac{2}{\sqrt{2^2+3^2+6^2}},\frac{3}{\sqrt{2^2+3^2+6^2}},\frac{6}{\sqrt{2^2+3^2+6^2}})(\frac{2}{7},\frac{3}{7},\frac{6}{7})(.28,.42,.85)$

Option $C$ is correct.