2. Questions Bank
  3. JEE Main & Advanced
  4. Mathematics
  5. Applications of Derivatives

JEE Main & Advanced Mathematics Applications of Derivatives Question Bank Increasing and Decreasing Function

  • question_answer
    \[2{{x}^{3}}-6x+5\] is an increasing function if [UPSEAT 2003]

    A)            \[0<x<1\]

    B)            \[-1<x<1\]

    C)            \[x<-1\] or \[x>1\]

    D)            \[-1<x<-1/2\]

    Correct Answer: C

    Solution :

               Let \[f(x)=2{{x}^{3}}-6x+5\] Þ \[{f}'(x)=6{{x}^{2}}-6>0\]            Þ \[{{x}^{2}}-1>0\]Þ \[(x-1)\] \[(x+1)>0\]Þ\[x>1\] or \[x<-1\].


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