2. Solved Papers
  3. J & K CET Engineering

J & K CET Engineering J and K - CET Engineering Solved Paper-2003

  • question_answer
    If \[{{b}^{2}}-4ac=0\]and \[a>0,\]then domain of the function \[f(x)=\log \{(a{{x}^{2}}+bx+c)\,\,(x+1)\}\] is

    A)  \[R-\left( -\frac{b}{2a} \right)\]

    B)  \[R-(-\infty ,\,\,-1)\]

    C)  \[(-1,\infty )-\left\{ -\frac{b}{2a} \right\}\]

    D)  \[R-\left( \left\{ -\frac{b}{2a} \right\}\cap (-\infty ,-1) \right)\]

    Correct Answer: C

    Solution :

    Given that, \[f(x)\log \{(a{{x}^{2}}+bx+c)\,\,(x+1)\}\,\] \[=\log (a{{x}^{2}}+bx+c)+\log (x+1)\] For \[f(x)\] to be defined \[a{{x}^{2}}+bx+c>0\] and \[x+1>0\] \[\Rightarrow \] \[x>-1\] Hence, option [c] is correct.


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