हिंदी

If a line makes angles π2,34π and π4 with x, y, z axis, respectively, then its direction cosines are ______.

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प्रश्न

If a line makes angles `pi/2, 3/4 pi` and `pi/4` with x, y, z axis, respectively, then its direction cosines are ______.

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उत्तर

If a line makes angles `pi/2, 3/4 pi` and `pi/4` with x, y, z axis, respectively, then its direction cosines are `+- (- 1/sqrt(2) 1/sqrt(2))`.

Explanation:

The direction cosines are `cos  pi/2, cos  3/4 pi, cos  pi/4`

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

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अध्याय 12: Introduction to Three Dimensional Geometry - Solved Examples [पृष्ठ २३३]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 12 Introduction to Three Dimensional Geometry
Solved Examples | Q 20 | पृष्ठ २३३

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