Find the direction cosines of a vector which is equally inclined to the x - axis, y - axis and z - axis.
Direction cosines of a vector l, m, n are related to each other as
Now given that equally inclined to three axes with an angle of θ. Then direction cosines l, m, n are
l = m = n = cosθ
Putting values of direction cosines in equation,
Cos2θ + Cos2θ + Cos2θ = 1
3Cos2θ = 1
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