2. Sample Papers
  3. JEE Main & Advanced

JEE Main & Advanced Sample Paper JEE Main Sample Paper-25

  • question_answer
    A plane meets coordinate axes at P, Q are R respectively such that position vector of centroid of \[\Delta PQR\] is \[2\hat{i}-5\hat{j}+8\hat{k}\], then the equation of plane is

    A)  \[\vec{r}.\left( 20\hat{i}-\hat{j}+5\hat{k} \right)=120\]

    B)  \[\vec{r}.\left( 20\hat{i}-8\hat{j}+5\hat{k} \right)=120\]

    C)  \[\vec{r}.\left( 20\hat{i}-8\hat{j}+5\hat{k} \right)=2\]

    D)  \[\vec{r}.\left( 20\hat{i}-8\hat{j}+5\hat{k} \right)=20\]

    Correct Answer: B

    Solution :

    G(2, -5, 8) \[\therefore \] P(6, 0, 0), Q (0, -15, 0) and \[R(0,0,24)\] \[\therefore \] Equation of plane is \[\frac{x}{6}\,+\frac{y}{-15}+\frac{z}{24}=1\]or \[\vec{r}.(20\hat{i}-8\hat{j}+5\hat{k})=120\]


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