J & K CET Engineering J and K - CET Engineering Solved Paper-2004

  • question_answer
    If \[f(x)={{\left( \frac{x}{1-|x|} \right)}^{1/2002}},\] then \[{{D}_{f}}\] is

    A)  \[R-[-1,\,1]\]

    B)  \[\{-\infty ,1\}\]

    C)  \[\{-\infty ,-1\}\cup (0,1)\]

    D)  None of the above

    Correct Answer: C

    Solution :

    \[f(x)={{\left[ {{\left( \frac{x}{1-|x|} \right)}^{1/2}} \right]}^{\frac{1}{1001}}}\] \[f(x)\] is defined, if \[\frac{x}{1-|x|}>0\] ie, \[x>0,1-|x|>0\] and \[x<0,\,\,1-|x|<0\] \[\Rightarrow \] \[x>0,|x|<1\] and \[x<0,|x|>1\] \[\Rightarrow \] \[x\in (0,1)\] and \[x\in (-\infty ,-1)\] \[\therefore \] \[x\in (-\infty ,-1)\,\cup \,(0,1)\]


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