The line makes angles α, β and γ with x-axia and z-axis respectively then cos 2α + cos 2β + cos 2γ is equal to (a) 2
(b) 1
(c) -2
(d) -1

Step-by-step explanation:

Given that lines makes an angle α, β, γ with x - axis, y - axis and z - axis respectively.

So, By definition of direction cosines,

So,

On multiply by 2 on both sides we get

can be further rewritten as

Hence,

So, option (d) is correct.

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Direction cosines of a line segment is defined as the cosines of the angle which a line makes with the positive direction of respective axis.

The scalar components of unit vector always give direction cosines.

The scalar components of a vector gives direction ratios.

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step-by-step explanation:

the x's and the y's both go up the same amount each time, therefore it will be a linear function because it will go in a straight line when drawn on a graph.

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step-by-step explanation: