JEE Main & Advanced Mathematics Differentiation Question Bank Differentiation of implicit function Parametric

  • question_answer
    If \[y=\frac{1}{4}{{u}^{4}},u=\frac{2}{3}{{x}^{3}}+5\], then \[\frac{dy}{dx}=\]         [DSSE 1979]

    A)            \[\frac{1}{27}{{x}^{2}}{{(2{{x}^{3}}+15)}^{3}}\]

    B)            \[\frac{2}{27}x{{(2{{x}^{3}}+5)}^{3}}\]

    C)            \[\frac{2}{27}{{x}^{2}}{{(2{{x}^{3}}+15)}^{3}}\]

    D)            None of these

    Correct Answer: C

    Solution :

               \[\frac{dy}{dx}=\frac{dy}{du}.\frac{du}{dx}={{u}^{3}}.2{{x}^{2}}\]                         \[={{\left( \frac{2}{3}{{x}^{3}}+5 \right)}^{3}}.2{{x}^{2}}=\frac{2}{27}{{x}^{2}}{{(2{{x}^{3}}+15)}^{3}}\].


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