Question

The coordinates of a point P are(3, 12, 4) w.r.t origin O, then the direction cosines of OP are

• A. 3, 12, 4
• B. $\frac{1}{4},\frac{1}{3},\frac{1}{2}$
• C. $\frac{3}{\sqrt{13}},\frac{1}{\sqrt{13}},\frac{2}{\sqrt{13}}$
• D. $\frac{3}{13},\frac{12}{13},\frac{4}{13}$

Answer 1

Answer: (D)

D.r's of OP are (3, 12, 4)
also $\sqrt{ 3^2 + 12^2 + 4^2} = 13$
D,c's are $\left( \frac{3}{13},\frac{12}{13},\frac{4}{13} \right)$