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If a line in the space makes angle $ \alpha, \beta, \gamma $ with the coordinate axes, then $ \cos 2\alpha + \cos 2\beta + \cos 2\gamma + \sin^{2}\alpha + \sin^{2}\beta + \sin^{2}\gamma $ equals

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Sum of squares of direction cosines ($l^2+m^2+n^2$) is always 1.

Updated On: Apr 10, 2026

-1
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1
2

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The Correct Option is C

Solution and Explanation

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If a line in the space makes angle \( \alpha, \beta, \gamma \) with the coordinate axes, then \( \cos 2\alpha + \cos 2\beta + \cos 2\gamma + \sin^{2}\alpha + \sin^{2}\beta + \sin^{2}\gamma \) equals

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The Correct Option is C

Solution and Explanation

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