Home
Class 12
MATHS
If |a|=2a n d|b|=3 and adotb=0,t h e n(a...

If `|a|=2a n d|b|=3` and `adotb=0,t h e n(axx(axx(axx(axxb))))` is equal to `48 hat b` b. `-48 hat b` c. `48 hat a` d. `-48 hat a`

A

16 a

B

16b

C

`-16a`

D

`-16b`

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • ADDITION AND MULTIPLICATION OF VECTORS

    ML KHANNA|Exercise Problem Set (3) (TRUE AND FALSE) |3 Videos

  • ADDITION AND MULTIPLICATION OF VECTORS

    ML KHANNA|Exercise Problem Set (3) (FILL IN THE BLANKS) |8 Videos

  • ADDITION AND MULTIPLICATION OF VECTORS

    ML KHANNA|Exercise Problem Set (2) (FILL IN THE BLANKS) |23 Videos

  • AREA OF CURVES

    ML KHANNA|Exercise SELF ASSESSEMENT TEST|16 Videos

Similar Questions

Explore conceptually related problems

If |a|=2 and |b|=3 and a.b=0, then (a xx(a xx(a xx(a xx b)))) is equal to 48hat b b.-48hat b c.48widehat a d.-48widehat a

(0.3467+0.1333) is equal to 0.48 (b) 0.48 (c) 0.4801 (d) 0.48

If vec a=2 hat i-3 hat j- hat k\ a n d\ b= hat i+4 hat j-2 hat k ,\ t h e n\ vec axx vec b= a. 10 hat i+2 hat j+11 hat k b. 10 hat i+3 hat j+11 hat k c. 10 hat i-3 hat j+11 hat k d. 10 hat i-2 hat j-10 hat k

vec a , vec b ,a n d vec c are unimodular and coplanar. A unit vector vec d is perpendicular to then. If ( vec axx vec b)xx( vec cxx vec d)=1/6 hat i-1/3 hat j+1/3 hat k , and the angel between vec aa n d vec b is 30^0,t h e n vec c is a. ( hat i-2 hat j+2 hat k)//3 b. (- hat i+2 hat j-2 hat k)//3 c. (2 hat i+2 hat j- hat k)//3 d. (-2 hat i-2 hat j+ hat k)//3

Let two non-collinear unit vector hat a a n d hat b form an acute angle. A point P moves so that at any time t , the position vector O P(w h e r eO is the origin) is given by hat acost+ hat bsintdotW h e nP is farthest from origin O , let M be the length of O Pa n d hat u be the unit vector along O Pdot Then (a) hat u=( hat a+ hat b)/(| hat a+ hat b|)a n dM=(1+ hat adot hat b)^(1//2) (b) hat u=( hat a- hat b)/(| hat a- hat b|)a n dM=(1+ hat adot hat )^(1//2) (c) hat u=( hat a+ hat b)/(| hat a+ hat b|)a n dM=(1+2 hat adot hat b)^(1//2) (d) hat u=( hat a- hat b)/(| hat a- hat b|)a n dM=(1+2 hat adot hat b)^(1//2)

vec a=(hat i+hat j+hat k),vec a*vec b=1 and vec a xxvec b=hat j-hat k, then hat b is hat i-hat j+hat k b.2hat j-hat k c.hat i d.2hat i

Let vec a=hat i+hat j;vec b=2hat i-hat k. Then vector vec r satisfying vec r xxvec a=vec b xxvec a and vec r xxvec b=vec a xxvec b is hat i-hat j+hat k b.3hat i-hat j+hat k c.3hat i+hat j-hat k d.hat i-hat j-hat k

Let vec aa n d vec b be mutually perpendicular unit vectors. Then for any arbitrary vec r , a. vec r=( vec rdot hat a) hat a+( vec rdot hat b) hat b+( vec rdot( hat axx hat b))( hat axx hat b) b. vec r=( vec rdot hat a)-( vec rdot hat b) hat b-( vec rdot( hat axx hat b))( hat axx hat b) c. vec r=( vec rdot hat a) hat a-( vec rdot hat b) hat b+( vec rdot( hat axx hat b))( hat axx hat b) none of these

If hat a , hat b ,a n d hat c are three unit vectors, such that hat a+ hat b+ hat c is also a unit vector and theta_1,theta_2a n dtheta_3 are angles between the vectors hat a , hat b ; hat b , hat ca n d hat c , hat a respectively, then among theta_1,theta_2,a n dtheta_3dot a. all are acute angles b. all are right angles c. at least one is obtuse angle d. none of these

Let vec a= hat i+ hat j+ hat k , vec b= hat i- hat j+ hat ka n d vec c= hat i- hat j- hat k be three vectors. A vector vec v in the plane of vec aa n d vec b , whose projection on vec c is 1/(sqrt(3)) is given by a. hat i-3 hat j+3 hat k b. -3 hat i-3 hat j+3 hat k c. 3 hat i- hat j+3 hat k d. hat i+3 hat j-3 hat k

ML KHANNA-ADDITION AND MULTIPLICATION OF VECTORS -Problem Set (3) (MULTIPLE CHOICE QUESTIONS)
  1. a xx [ a xx (a xx b)] equals

    Text Solution

    |

  2. If the vectors veca and vecb are mutually perpendicular, then veca xx ...

    Text Solution

    |

  3. If |a|=2a n d|b|=3 and adotb=0,t h e n(axx(axx(axx(axxb)))) is equal t...

    Text Solution

    |

  4. [a " " b " "axxb] +[a.b]^(2) =

    Text Solution

    |

  5. If a = 1,2,4, b =2,-3,-1, c=1,4-4, then the vector a xx(b xxc) is orth...

    Text Solution

    |

  6. The magnitudes of vectors vec a , vec b and vec c are respectively 1...

    Text Solution

    |

  7. For non-coplanar vectors a, b and c, abs((a times b)*c)=abs(a) abs(b) ...

    Text Solution

    |

  8. Let veca = 2i + j + k, and b = i+ j if c is a vector such that veca ....

    Text Solution

    |

  9. Let a =2i+j-2k and b=i+j. If c is a vector such that a.c = |c|,|c-a| =...

    Text Solution

    |

  10. Let the unit vectors a and b be perpendicular and the unit vector c be...

    Text Solution

    |

  11. The equation of the plane containing the line vecr= veca + k vecb and ...

    Text Solution

    |

  12. ( axxb) xx (a xxc ).d equals

    Text Solution

    |

  13. If a,b,c and d be four vectors, then (a xxb). (c xx d) + ( b xx c) . ...

    Text Solution

    |

  14. If the non-zero vectors a and b are perpendicular to each other, then ...

    Text Solution

    |

  15. Let veda,vecb,vecc be three noncolanar vectors and vecp,vecq,vecr are ...

    Text Solution

    |

  16. Let a,b,c be any threee non zero non-coplanar vectors, then any vecto...

    Text Solution

    |

  17. If a,b,c and p,q,r are reciprocal systemm of vectors, then axxp+bxxq+c...

    Text Solution

    |

  18. If a.(b xx c) = 3 then

    Text Solution

    |

  19. Let a,b,c be three non-coplanar vectors and r be any vector in space s...

    Text Solution

    |

  20. Unit vector vecc is inclined at an angle theta to unit vectors ve...

    Text Solution

    |