Home
Class 12
MATHS
If D, E, F are respectivley the mid poin...

If D, E, F are respectivley the mid points of AB, AC and BC respectively in a triangle ABC, then `vec BE + vec AF =`

A

`vec DC`

B

`1/2 vec BF`

C

`2 vec BF`

D

`3/2 vec BF`

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • THREE DIMENSIONAL GEOMETRY

    HIMALAYA PUBLICATION|Exercise QUESTION BANK|194 Videos

Similar Questions

Explore conceptually related problems

If D, E and F are respectively, the mid-points of AB, AC and BC in DeltaABC , then BE + AF is equal to

If D, E and F are three points on the sides BC, CA and AB, respectively, of a triangle ABC such that the lines AD, BE and CF are concurrent, then show that " "(BD)/(CD)*(CE)/(AE)*(AF)/(BF)=-1

In a Δ ABC, D,E,F are respectively, the mid- points of BC,CA, and AB. If the lengths of side AB, BC and CA are 7 cm, 8 cm, 9 cm, respectively, find the perimeter of Δ DEF.

D,E and F are respectively the mid-points of the sides BC, CA and AB of triangle ABC show that (i) BDEF is a parallelogram. (ii) ar (DEF) = 1/4 ar (ABC) (iii) ar (BDEF) = 1/2 ar (ABC)

Prove that the area of the euilateral traingle described on the side of a square is half the area of the equilatiral triangle described on it's square . OR In Delta ABC D,E, F are the midpoints of te sides BC, AC and AB respectively. Find the rations of the areas of Delta DEF Delta ABC

D, E and F are respectively the mid-points of sides AB, BC and CA of Delta ABC . Find the ratio of the areas of Delta DEF and Delta ABC .

In Delta ABC , D and E are the mid-points of AB and AC respectively, then the area of Delta ADE is :

If D , E and F are the mid-points of the sides BC , CA and AB respectively of the DeltaABC and O be any point, then prove that OA+OB+OC=OD+OE+OF

D,Eand F are respectively the mid - points of sides AB, BC and CA of DeltaABC . Find the ratio of the areas of DeltaDEF and DeltaABC.

HIMALAYA PUBLICATION-VECTORS AND THEIR APPLICATIONS-QUESTION BANK
  1. If vec a xx vec b = vec c and vec b xx vec c = vec a then

    Text Solution

    |

  2. If vec a, vec b, vec c are linearly independent vectors and Delta = |(...

    Text Solution

    |

  3. If pi(1) and pi(2) be two planes determined by the pairs of vectors ve...

    Text Solution

    |

  4. If vec a xx vec b = vec c and vec b xx vec c = vec a then

    Text Solution

    |

  5. For any vector vec r, (vec r . i)^(2) + (vec r .j)^(2) + (vec r . k )^...

    Text Solution

    |

  6. If |vec a - vec b| = |vec a| = |vec b| =1 then the angle between vec a...

    Text Solution

    |

  7. If |vec a| = 3, |vec b| = 5, and |vec c| = 4 and vec a + vec b + vec c...

    Text Solution

    |

  8. Let vec a, vec b and vec c be three vectors. Then scalar triple produc...

    Text Solution

    |

  9. If vec u, vec nu, vec w are three non-coplanar vectors, then (vec u + ...

    Text Solution

    |

  10. A unit vector perpendicular to the plane of vec a = 2i-6j-3k and vec b...

    Text Solution

    |

  11. A vector coplanar with vector i+j and j+k and parallel to the vector 2...

    Text Solution

    |

  12. Let vec a = 2i+j-2k and vec b = i+j. If vec c is a vector such that ...

    Text Solution

    |

  13. The volume of the tetracedron formed by the points (1,1,1) (2,1,3),(3,...

    Text Solution

    |

  14. If |vec a| = 4, |vec b| = 2, |vec c| = 6 and each of the angles betwee...

    Text Solution

    |

  15. The area of the parallelogram with vec a and vec b as adjacent sides i...

    Text Solution

    |

  16. If the triangle with vertices 2i+j, 2j+k, mk+i, has centroid at i+j+k,...

    Text Solution

    |

  17. Let vec a = i-2j+3k, vec b = 3i+3j-k and vec c = di + j + (2d-1)k. If ...

    Text Solution

    |

  18. If [vec a, vec b, vec c] = 3 then the volume (in cubic units) of the p...

    Text Solution

    |

  19. If D, E, F are respectivley the mid points of AB, AC and BC respective...

    Text Solution

    |

  20. If (vec a xx vec b) xx vec c = vec a xx (vec b xx vec c), where vec a,...

    Text Solution

    |