JEE Main & Advanced Sample Paper JEE Main - Mock Test - 6

  • question_answer
    The minor axis of the ellipse with foci \[\left( \pm 2,0 \right)\] and eccentricity\[\frac{1}{3}\] is

    A) 4

    B) 3

    C) \[8\sqrt{2}\]

    D) \[4\sqrt{2}\]

    Correct Answer: C

    Solution :

    [c] : The ellipse is\[\frac{{{x}^{2}}}{{{a}^{2}}}+\frac{{{y}^{2}}}{{{b}^{2}}}=1\] \[{{S}_{1}}\equiv (-2,0),S\equiv (2,0)\] \[\Rightarrow \]\[{{S}_{1}}S=4=2ae=2a\times \frac{1}{3}\Rightarrow a=6\] \[\therefore \]\[{{b}^{2}}={{a}^{2}}(1-{{e}^{2}})=36\left( 1-\frac{1}{9} \right)=32\] \[b=4\sqrt{2}\]\[\therefore \]Minor axis\[=2b=8\sqrt{2}\].

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