

MCQOPTIONS
Saved Bookmarks
1. |
If a line has direction ratios < a + b, b + c, c + a >, then what is the sum of the squares of its direction cosines? |
A. | (a + b + c)2 |
B. | 2 (a + b + c) |
C. | 3 |
D. | 1 |
Answer» E. | |