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Question
If α, β, γ are the angles that a line makes with the positive direction of x, y, z axis, respectively, then the direction cosines of the line are ______.
Options
sin α, sin β, sin γ
cos α, cos β, cos γ
tan α, tan β, tan γ
cos2α, cos2β, cos2γ
Solution
If α, β, γ are the angles that a line makes with the positive direction of x, y, z axis, respectively, then the direction cosines of the line are cos α, cos β, cos γ.
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