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If a12,12,a are the direction cosines of some vector, then find a - Mathematics

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प्रश्न

If `1/2, 1/sqrt(2), "a"` are the direction cosines of some vector, then find a

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उत्तर

Given `1/2, 1/sqrt(2), "a"` are the direction cosines of some vector, then

`(1/2)^2 + (1/sqrt(2))^2 + "a"^2` = 1

`1/4 + 1/2 + "a"^2` = 1

`(1 + 2)/4 + "a"^2` = 1

a2 = `1 - 3/4`

= `(4 - 3)/4`

= `1/4`

a = `+-  1/2`

If l, m, n are direction cosines of a vector then l2 + m2 + n2 = 1

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 8: Vector Algebra - Exercise 8.2 [पृष्ठ ६८]

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सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
पाठ 8 Vector Algebra
Exercise 8.2 | Q 5 | पृष्ठ ६८

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