Each of the angles and that a given line makes with the positive y- and z-axes, respectively, is half of the angle that this line makes with the positive x-axis. Then the sum of all possible values of the angle is
- 2
- 3 4
- 3 2
Answer
(3) 3 4
Solution
Let the angle with the x-axis be ; then = = 2, 0 .
2 + 2 + 2 = 1
2 + 2 2 2 = 1
2 + 1 + = 1
( + 1) = 0
= 0 or = -1
= 2 or =
= 4 or = 2 (both valid)
sum of possible values of = 4 + 2 = 3 4
Answer: (3)