JEE Main & Advanced Mathematics Conic Sections Question Bank Hyperbola

  • question_answer
    The straight line \[x+y=\sqrt{2}p\]will touch the hyperbola \[4{{x}^{2}}-9{{y}^{2}}=36\], if               [Orissa JEE 2003]

    A)            \[{{p}^{2}}=2\]                          

    B)            \[{{p}^{2}}=5\]

    C)            \[5{{p}^{2}}=2\]                        

    D)            \[2{{p}^{2}}=5\]

    Correct Answer: D

    Solution :

               The condition for the line \[y=mx+c\] will touch the hyperbola \[\frac{{{x}^{2}}}{{{a}^{2}}}-\frac{{{y}^{2}}}{{{b}^{2}}}=1\] is \[{{c}^{2}}={{a}^{2}}{{m}^{2}}\]\[-{{b}^{2}}\] Here \[m=-1\], \[c=\sqrt{2}p,\] \[{{a}^{2}}=9,\,\,{{b}^{2}}=4\]                    \ We get \[2{{p}^{2}}=5.\]


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