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

JEE Main & Advanced Mathematics Applications of Derivatives Question Bank Maxima and Minima

  • question_answer
    The two parts of 100 for which the sum of double of first and square of second part is minimum, are

    A)            50, 50

    B)            99, 1

    C)            98, 2

    D)            None of these

    Correct Answer: B

    Solution :

               Let one number is\[(100-x)\] and then another is x. Therefore \[f(x)=2(100-x)+{{x}^{2}}={{x}^{2}}-2x+200\]                          \[f'(x)=0\Rightarrow 2x-2=0\Rightarrow x=1\]            Here \[{f}''\,(x)=2>0\]            Therefore function is minimum at \[x=1\]            So the numbers are 99 and 1.


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