2. Questions Bank
  3. JEE Main & Advanced
  4. Mathematics
  5. Three Dimensional Geometry

JEE Main & Advanced Mathematics Three Dimensional Geometry Question Bank System of Co-ordinates, Direction cosines and direction ratios, Projection

  • question_answer
    If the points \[A(9,\,\,8,\,-10)\],\[B(3,\,\,2,\,\,-4)\]and \[C(5,\,\,4,\,-6)\]be collinear, then the point C divides the line \[AB\] in the ratio

    A)            2 : 1

    B)            3 : 1

    C)            1 : 2

    D)            ?1 : 2

    Correct Answer: A

    Solution :

               Let point C divides the line AB in the ratio \[1\,\,:\,\,\lambda \]. \[\therefore \,\,5=\frac{9\lambda +3}{\lambda +1}\,\,\Rightarrow \,\,4\lambda =2\,\,\Rightarrow \,\,\lambda =\frac{1}{2}\]            Hence required ratio is 2 : 1.


You need to login to perform this action.
You will be redirected in 3 sec spinner