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If |a|=3,|b|=4a n d the angle between aa...

If `|a|=3,|b|=4a n d` the angle between `aa n db` is `120^0` , then find the value of `|4a+3b|dot`

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`|4veca+3.vecb|=sqrt((4veca+3vecb).(4veca+3vecb))`
`sqrt(16|veca|^(2)+9|vecb|^(2)+24veca.vecb)`
`sqrt(144 + 144 + 24 xx 3xx4 xx(-1/2))`
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CENGAGE-DIFFERENT PRODUCTS OF VECTORS AND THEIR GEOMETRICAL APPLICATIONS -Exercise
  1. Show that |veca|vecb+|vecb|veca is perpendicular to |veca|vecb-|vecb|...

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  2. If the vertices A,B, C of a triangle ABC are (1,2,3),(-1, 0,0), (0, 1,...

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  3. If |a|=3,|b|=4a n d the angle between aa n db is 120^0 , then find the...

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  4. If vectors hati-2xhatj-3yhatk and hati+ 3 x hatj + 2yhatk are orthogon...

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  5. Let veca vecb and vecc be pairwise mutually perpendicular vectors, suc...

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  6. If veca+vecb+vecc =0, |veca|=3, |vecb|=5, |vecc|=7 then the angle betw...

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  7. If the angle between unit vectors veca and vecb is 60^(@) . Then find ...

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  8. Let vecu=hai+hatj,vecv=hati-hatj and vecw=hati+2hatj+3hatk. If hatn is...

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  9. A , B , C , D are any four points, prove that vec A B dot vec C D+ ...

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  10. P(1,0,-1), Q(2,0,-3),R(-1,2,0)a n dS(,-2,-1), then find the projection...

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  11. If the vectors 3 vec p+ vec q ;5p-3 vec qa n d2 vec p+ vec q ;3 vec p-...

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  12. Let vecA and vecB be two non-parallel unit vectors in a plane. If (alp...

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  13. If veca ,vecb, vec c are three vectors such that veca + 2 vecb + vecc ...

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  14. If veca and vecb are unit vectors, then find the greatest value of |ve...

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  15. Constant forces P1= hat i+ hat j+ hat k ,P2= hat i+2 hat j- hat ka n d...

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  16. Find |veca|and|vecb|, if (veca+vecb)*(veca-vecb)=8and|veca|=8|vecb|.

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  17. If A ,B ,C ,D are four distinct point in space such that A B is not...

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  18. If veca=2hati+ 3hatj-5hatk,vecb =m hati+nhatj +12 hatk and veca xx vec...

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  19. If |veca|=2, |vecb|=5 and |vecaxxvecb|=8 then find the value of veca.v...

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  20. If veca xx vecb = vecb xx vecc ne 0 where veca , vecb and vecc are co...

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