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The direction cosines of the vector (2i^+2j^-k^) are ______. - Mathematics

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प्रश्न

The direction cosines of the vector `(2hati + 2hatj - hatk)` are ______.

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उत्तर

The direction cosines of the vector `(2hati + 2hatj - hatk)` are `2/3, 2/3, (-1)/3`.

Explanation:

Direction cosines of `(2hati + 2hatj - hatk)` are

`2/sqrt(4 + 4 + 1)`, `2/sqrt(4 + 4 + 1)`, `(-1)/sqrt(4 + 4 + 1)`

i.e., `2/3, 2/3, (-1)/3`

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अध्याय 12: Introduction to Three Dimensional Geometry - Exercise [पृष्ठ २३९]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 12 Introduction to Three Dimensional Geometry
Exercise | Q 38 | पृष्ठ २३९

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