Question

The direction co-sines of the line which bisects the angle between positive direction of Y and Z axes are ______.

Options

• `0, 1/sqrt2, 1/sqrt2`

• `1/sqrt2,1/sqrt2,0`

• `1/sqrt2,1/sqrt2,1/sqrt2`

• `1/sqrt2,0,1/sqrt2`

Answer 1

The direction co-sines of the line which bisects the angle between positive direction of Y and Z axes are `underline(0, 1/sqrt2, 1/sqrt2)`.

Explanation:

A point lie on the line which bisects the angle between positive direction of Y and Z axes on (0, a, a)

Direction ratio of line passing through origin and point (O, a, a) is (0, a, a)

Direction cosine of a line is 

`0/(sqrt(0 + "a"^2 + "a"^2)), "a"/sqrt(2"a"^2), "a"/sqrt(2"a"^2)`

`= 0, 1/sqrt2, 1/sqrt2`