मराठी

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

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प्रश्न

The direction cosines of vector `(2hat"i" + 2hat"j" - hat"k")` are ______.

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उत्तर

The direction cosines of vector `(2hat"i" + 2hat"j" - hat"k")` are `2/3, 2/3, (-1)/3`.

Explanation:

Let `vec"a" = 2hat"i" + 2hat"j" - hat"k"`

Direction ratios of `vec"a"` are 2, 2, – 1

So, the direction cosines are `2/sqrt(4 + 4 + 1)`

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

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

⇒ `2/3, 2/3, (-1)/3`

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पाठ 11: Three Dimensional Geometry - Exercise [पृष्ठ २३९]

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

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