मराठी

If |a→×b→|=3 and a→.b→ = – 3, then angle between a→ and b→ is ______. - Mathematics

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प्रश्न

If `|veca xx vecb| = sqrt(3)` and `veca.vecb` = – 3, then angle between `veca` and `vecb` is ______.

पर्याय

  • `(2π)/3`

  • `π/6`

  • `π/3`

  • `(5π)/6`

MCQ
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उत्तर

If `|veca xx vecb| = sqrt(3)` and `veca.vecb` = – 3, then angle between `veca` and `vecb` is `underlinebb((5π)/6)`.

Explanation:

Given,

`|veca xx vecb| = sqrt(3)` and `veca.vecb` = – 3

Then `|veca||vecb| sin θ = sqrt(3)`  ...(i)

and `|veca||vecb| cos θ` = – 3  ...(ii)

On dividing (i) by (ii), we get

`sinθ/cosθ = sqrt(3)/-3 = (-1)/sqrt(3)`

`\implies` tan θ = `- tan (π/6)`

`\implies` θ = `π - π/6`

= `(5π)/6`

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