हिंदी

If a line makes an angle of 30°, 60°, 90° with the positive direction of x, y, z-axes, respectively, then find its direction cosines.

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प्रश्न

If a line makes an angle of 30°, 60°, 90° with the positive direction of x, y, z-axes, respectively, then find its direction cosines.

योग
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उत्तर

The direction cosines of a line which makes an angle of α, β, γ with the axes, are cosα, cosβ, cosγ

Therefore, D.C.’s of the line are cos30°, cos60°, cos90°

i.e., `+(sqrt(3)/2, 1/2, 0)`

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अध्याय 11: Three Dimensional Geometry - Solved Examples [पृष्ठ २२५]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
अध्याय 11 Three Dimensional Geometry
Solved Examples | Q 3 | पृष्ठ २२५

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