Home
Class 12
MATHS
If the direction cosines of a line are 1...

If the direction cosines of a line are `1/c,1/c,1/c` rthen (A) `c.0` (B) `0ltclt1` (C) `c=+-sqrt(3)` (D) `cgt2`

A

`0 lt c lt 1`

B

`c gt 2`

C

` c gt2`

D

` c = pm sqrt(3)`

Text Solution

Verified by Experts

The correct Answer is:
d
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 the direction cosines of a line are ((1)/(c ) , (1)/(c ), (1)/(c )) then :

If the direction cosines of a straighat line are k,k,k the (A) kgt0 (B) 0ltklt1 (C) k=1 (D) k=1/sqrt(3) or -1/sqrt(3)

The direction cosines of x-axis are (A) 0,0,1 (B) 1,0,0 (C) 0,1,0 (D) 0,1,1

The direction cosines of line joining (1,-1,1) and (-1,1,1) are (A) 2,-2,0 (B) 1,-1,0 (C) 1/sqrt(2)-1/sqrt(2),0 (D) none of these

The direction cosines of any normal to the xy-plane are (A) 1,0,0 (B) 0,1,0 (C) 1,1,0 (D) 0,01

A straight line L on the xy-plane bisects the angle between OX and OY. What are the direction cosines of L? a.(:(1/sqrt(2)),(1/sqrt(2)),0:)b(:(1/2),(sqrt(3)/2),0:)c.(:0,0,1:)d(:(2/3),(2/3),(1/3):)

Let a,b,c in R such that a^(2)+b^(2)+c^(2)=2bc,a^(2)+b^(2)+c^(2)!=0 . Then which of the following points lie on the line ax+by+c=0 , is : (A) (-1,2) (B) (1,2) (C) (-1,-2) (D) (2,-1)

If a,b,c real in G.P.then the roots of the equation ax^(2)+bx+c=0 are in the ratio (1)/(2)(-1+sqrt(3)) b.(1)/(2)(1-i sqrt(3)) c.(1)/(2)(-1-i sqrt(3)) d.(1)/(2)(1+i sqrt(3))

If agt0, bgt0, cgt0 and the minimum value of a^2(b+c)+b^2(c+a)+c^2(a+b) is kabc, then k is (A) 1 (B) 3 (C) 6 (D) 4

If a b+b c+c a=0 , then what is the value of (1/(a^2-b c)+1/(b^2-c a)+1/(c^2-a b)) ? (a) 0 (b) 1 (c) 3 (d) a+b+c

MARVEL PUBLICATION-THREE DIMENSIONAL GEOMETRY-MULTIPLE CHOICE QUESTIONS
  1. A line makes 45^(@) with OX and equal angles with OY and OZ .Then the ...

    Text Solution

    |

  2. What is the angle between the two lines whose direction numbers are (s...

    Text Solution

    |

  3. If the line of the vector bar (r ) = lambda I + 2j - k makes angles a...

    Text Solution

    |

  4. The number of lines which are equally inclined to the axes is :

    Text Solution

    |

  5. The projection of the line segment joining the points A(-1,0,3) and B(...

    Text Solution

    |

  6. Direction Cosines of a normal to the XOY - plane are

    Text Solution

    |

  7. If the direction cosines of a line are 1/c,1/c,1/c rthen (A) c.0 (B) 0...

    Text Solution

    |

  8. A mirror and a source of light are situated at the origin O and at a...

    Text Solution

    |

  9. The direction Cosines of two lines at right angles are l(1),m(1),n(1)a...

    Text Solution

    |

  10. The graph of the equation x^2+y^2=0 in the three dimensional space is ...

    Text Solution

    |

  11. If the line OP of length r makes an angle alpha with the X - axis , an...

    Text Solution

    |

  12. l = m = n = 1 are the direction Cosines of

    Text Solution

    |

  13. STATEMENT-1 : The direction ratios of a line joining the points (0, 0,...

    Text Solution

    |

  14. Co - ordinates of the foot of the perpendicular from the point (a,b,c)...

    Text Solution

    |

  15. In three dimensional space , the equation xy = 0 represents

    Text Solution

    |

  16. In space , the equation 3x-4y=0 represents

    Text Solution

    |

  17. A line lies in ZX plane and makes 60^(@) with x - axis ,then direction...

    Text Solution

    |

  18. The ratio in which XOZ plane divides A(2,-3,1) and B(-1,4,5) is :

    Text Solution

    |

  19. If the line vec(OR) makes angles theta(1),theta(2),theta(3) with the ...

    Text Solution

    |

  20. The direction ratios of a line which is perpendicular to the two vect...

    Text Solution

    |