2. Solved Papers
  3. JAMIA MILLIA ISLAMIA

JAMIA MILLIA ISLAMIA Jamia Millia Islamia Solved Paper-2015

  • question_answer
    Let\[x=0\]be a polynomial of second degree. If\[f(x)\]and a, b, c are in AP, then\[x=0\]and\[f(|x|)\]Mare in

    A) AGP

    B) AP

    C) GP

    D) HP

    Correct Answer: B

    Solution :

    Let \[f(1)=f(-1)\]. Then, \[\Rightarrow \]               \[A+B+C=A-B-C\] \[\Rightarrow \]               \[B=0\] \[\therefore \]  \[f(x)=A{{x}^{2}}+C\] \[\Rightarrow \]               \[f'(x)=2Ax\] \[\Rightarrow \]\[f'(a)=2Aa,f'(b)=2Ab\,and\,\,f'(c)=2Ac\] Since, a, b, c are in AP. \[\therefore \]       2Aa, 2Ab, 2Ac are in AP. Hence,\[f'(a),f'(b),f'(c)\] are in AP.


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