Write the direction cosines of a line equally inclined to be three coordinate axes.

Explanation

As the given line is equally inclined with all three coordinate axis,
let it create angle `alpha` with all three coordinate axis.

Then,

Direction cosines will be `(cos alpha,cos alpha,cos alpha)`.

`:. cos^2alpha+cos^2alpha+cos^2alpha = 1`

`=>3cos^2alpha = 1`

`=>cos alpha = +-1/sqrt3`

When `cos alpha = 1/sqrt3`,

Direction cosines will be `(1/sqrt3,1/sqrt3,1/sqrt3)`.

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