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If |vec a|=8, |vec b|=3 and |vec axx vec...

If `|vec a|=8, |vec b|=3` and `|vec axx vec b|=12`, then the value of `vec a . vec b` is

A

`6 sqrt3 or -6sqrt3`

B

`8 sqrt3 or -8sqrt3`

C

`12 sqrt3 or -12sqrt3`

D

none of these

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PRADEEP PUBLICATION-VECTORS-EXERCISE
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  2. Find the angle between the vectors hat i-hat j and hat j-hat k.

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  3. The vector with initial point P(2,-3,5) and terminal point Q(3,-4,7) i...

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  4. If vec a * vec a=0 thenvec a is a

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  5. If vec a and vec b are proper vectors such that vec b= λ veca for some...

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  6. For any two vectors vec a and vec b, which of the following is not tru...

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  7. The area of the parallelogram whose adjacent sides are hat i+hat k and...

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  8. If the vectors from the origin to the points A and B are . vec a= a ha...

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  9. Given |quad vec a|=10,|quad vec b|=2 and vec a *vec b=12, find | vec a...

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  10. Direction cosines of hat i are ‘

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  11. The vectors -2 hat i+hat j +2 hatk, hat i+ λ hat j- hatk, 2hat i- hat...

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  12. If vec a,vec b,vec c are unit vectors such that vec a+vec b+ vec c= ve...

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  13. If |vec a|=8, |vec b|=3 and |vec axx vec b|=12, then the value of vec ...

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  14. If the vectors 2hat j +hat k and 3 hat i- hat j +4 hatk represent the ...

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  15. (hat i+hatj) xx (hat j+ hatk)*(hat k+ hat i) is equal to

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  16. If vec a, vec b and sqrt(3)veca-vec b are Unit Vectors, then the angle...

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  17. If |vec a|=8, |vec b|=3 and |vec axx vec b|=12, then the value of vec ...

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  18. If ABC is any triangle and D is the midpoint of side [BC], then vec (...

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  19. If vec b is a non-zero vector, then projection of vec a on vec b is

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  20. If vec a is a unit vector Perpendicular to the vectors vec b= hat i -h...

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