CEE Kerala Engineering CEE Kerala Engineering Solved Paper-2002

  • question_answer
    \[\underset{x\to 0}{\mathop{\lim }}\,\frac{1-\cos mx}{1-\cos mx}\]is equal to:

    A)  \[\frac{m}{n}\]                                

    B)                         \[\frac{{{m}^{2}}}{{{n}^{2}}}\]

    C)                         \[0\]                                    

    D)                         \[\frac{{{n}^{2}}}{{{m}^{2}}}\]

    E)                         \[\frac{n}{m}\]

    Correct Answer: B

    Solution :

    \[\underset{x\to 0}{\mathop{\lim }}\,\left( \frac{1-\cos mx}{1-\cos nx} \right)\] \[=\frac{{{m}^{2}}}{{{n}^{2}}}\underset{x\to 0}{\mathop{\lim }}\,\frac{2{{\sin }^{2}}(mx/2)}{{{(mx/2)}^{2}}}.\frac{{{(nx/2)}^{2}}}{2{{\sin }^{2}}(nx/2)}.\frac{{{m}^{2}}}{{{n}^{2}}}\] \[=\frac{{{m}^{2}}}{{{n}^{2}}}\]


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