JEE Main & Advanced Mathematics Functions Question Bank Functions

  • question_answer
    The function \[f(x)=\sin \left( \log (x+\sqrt{{{x}^{2}}+1}) \right)\] is            [Orissa JEE 2002]

    A)                    Even function

    B)            Odd function

    C)                    Neither even nor odd

    D)             Periodic function

    Correct Answer: B

    Solution :

               \[f(x)=\sin \,\left( \log \,(x+\sqrt{1+{{x}^{2}}}) \right)\]            Þ \[f(-x)=\sin \,[\log \,(-x+\sqrt{1+{{x}^{2}}})]\]            Þ \[f(-x)=\sin \,\log \left( (\sqrt{1+{{x}^{2}}}-x)\frac{(\sqrt{1+{{x}^{2}}}+x)}{(\sqrt{1+{{x}^{2}}}+x)} \right)\]            Þ \[f(-x)=\sin \,\log \,\left[ \frac{1}{(x+\sqrt{1+{{x}^{2}}})} \right]\]            Þ \[f(-x)=\sin \left[ \log {{(x+\sqrt{1+{{x}^{2}}})}^{-1}} \right]\]            Þ \[f(-x)=\sin \left[ -\log (x+\sqrt{1+{{x}^{2}}}) \right]\]            Þ \[f(-x)=-\sin \left[ \log (x+\sqrt{1+{{x}^{2}}}) \right]\]Þ \[f(-x)=-f(x)\]            \\[f(x)\] is odd function.


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