Home
Class 12
MATHS
Direction cosines of a line , for which ...

Direction cosines of a line , for which ` alpha = beta and gamma = 45^(@)`

A

`1/(sqrt(2)),pm1/2,pm1/2`

B

`pm1/2,pm1/(sqrt(2)),pm1/2`

C

` pm 1/2 , pm 1/2 ,1/(sqrt(2))`

D

`1/2,1/2,pm 1/(sqrt(2))`

Text Solution

Verified by Experts

The correct Answer is:
c
Promotional Banner

Topper's Solved these Questions

  • THREE DIMENSIONAL GEOMETRY

    MARVEL PUBLICATION|Exercise MULTIPLE CHOICE QUESTIONS|39 Videos

  • PLANE IN SPACE

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP- CHAPTERS 6,7,22|1 Videos

  • TRIGONOMETRIC FUNCTIONS

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP: CHAPTER 3-3.3|13 Videos

Similar Questions

Explore conceptually related problems

If alpha,beta ,gamma are direction angles of a line , then cos 2alpha + cos 2beta + cos 2 gamma =

Statement 1: If cos alpha,cos beta, and cos gamma are the direction cosines of any line segment,then cos^(2)alpha+cos^(2)beta+cos^(2)gamma=1. Statement 2: If cos alpha,cos beta,and cos gamma are the direction cosines of any line segment,then cos2 alpha+cos2 beta+cos2 gamma=1

If alpha, beta, gamma are direction angles of a line and alpha = 60^(@), beta = 45^(@) , then gamma =_________

If cosalpha, cosbeta, cosgamma be the direction cosines of a line, prove that sin^(2)alpha+sin^(2)beta+sin^(2)gamma=2 .

If direction angles of a line are alpha, beta, gamma such that alpha+beta=90^(@) , then (cos alpha+cos beta+cos gamma)^(2)=

If (l,m,n) are the direction cosines of a line then cos^(2)alpha+cos^(2)beta+cos^(2)gamma=

If cosalpha,cosbeta,cosgamma are the direction cosines of a vector veca , then cos2alpha+cos2beta+cos2gamma is equal to

If cos alpha, cos beta, cos gamma are the direction cosines of a line then the value of sin^(2) alpha + sin^(2) beta + sin^(2) gamma is__________

" If "(l,m,n)" are directional cosines of a line,then "cos^(2)alpha+cos^(2)beta+cos^(2)gamma=

If alpha, beta , gamma are direction-angles of a line, prove that (i) cos2alpha + cos 2 beta +cos2 gamma+ 1 = 0 . (ii) cos 2 alpha + cos 2 beta + cos 2 gamma = -1 .

MARVEL PUBLICATION-THREE DIMENSIONAL GEOMETRY-MULTIPLE CHOICE QUESTIONS
  1. If alpha,beta,gamma are the angles which a line makes with OX,OY and O...

    Text Solution

    |

  2. If alpha,beta ,gamma are direction angles of a line , then cos 2alpha ...

    Text Solution

    |

  3. Direction cosines of a line , for which alpha = beta and gamma = 45^(...

    Text Solution

    |

  4. If a line is inclined at 60^(@) and 30^(@) with the X-and Y-axes respe...

    Text Solution

    |

  5. The direction consines of a line which lies in XZ-plane and making an ...

    Text Solution

    |

  6. Show that no line in space can make angles (pi)/(6) and (pi)/(4) with ...

    Text Solution

    |

  7. If a line is equally inclines to co - ordinate to co - ordinate axes ,...

    Text Solution

    |

  8. Direction cosines of a line , whose direction ratios are -2,1,2 are

    Text Solution

    |

  9. If P is (-1,1,2) , then direction cosines of line OP are

    Text Solution

    |

  10. Direction cosines of the line passing through A(2,3,-1)and B(-3,-4,2) ...

    Text Solution

    |

  11. Find the value of p for which the line through the points A(4, 1, 2) a...

    Text Solution

    |

  12. Given P = (3,-6,10)and PQ = sqrt(17) . If direction cosines of line PQ...

    Text Solution

    |

  13. If l,m,n are direction cosines of a line , then vector li +mj+nk is a

    Text Solution

    |

  14. If |bar(u)| = sqrt(3) and bar(u) is equally inclined to co - ordinate...

    Text Solution

    |

  15. If |bar(u)|=2 and bar(u) makes angles of 60^(@) and 120^(@) with OX a...

    Text Solution

    |

  16. If a line makes angles theta(1), theta(2), theta(3) with the coordinat...

    Text Solution

    |

  17. Find the angle between the lines whose direction ratios are: 2,-3,4 ...

    Text Solution

    |

  18. If bar(a),bar(b),bar (c ) are pair wise mutually perpendicular vectors...

    Text Solution

    |

  19. If direction ratios of two lines are 2,-6,-3 and 4,3,-1 then directi...

    Text Solution

    |

  20. A line makes 45^(@) with OX and equal angles with OY and OZ .Then the ...

    Text Solution

    |