CEE Kerala Engineering CEE Kerala Engineering Solved Paper-2003

  • question_answer
    The points\[A(4,5,1),B(0,-1,-1),C(3,9,4)\]and \[D(-4,4,4)\]are:

    A)  collinear             

    B)  coplanar             

    C)         non-coplanar   

    D)         non-collinear

    E)  non-collinear and non-coplanar

    Correct Answer: B

    Solution :

    Equation of plane through the point A (4, 5,1) is \[a(x-4)+b(y-5)+c(z-1)=0\]              ...(i) Let points\[B(0,-1,-1)\]and C (3, 9, 4) lies on equation (i), if \[a(0-4)+b(-1-5)+c(-1-1)=0\] \[\Rightarrow \]         \[2a+3b+c=0\]                        ...(ii) and       \[-a+4b+3c=0\]  ...(iii) On solving Eqs. (ii) and (iii), we get                 \[\frac{a}{5}=\frac{b}{-7}=\frac{c}{11}\] \[\therefore \]\[5(x-4)-7(y-5)+11(z-1)=0\] \[\Rightarrow \]\[5x-7y+11z+4=0\] is the plane through A, B and C. Now,\[D(-4,4,4)\]lies on it, if \[-20-28+44+4=0\]which is true. \[\therefore \]Points A, B, C and D are coplanar.


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