MCQ
If $f(x) = \left\{ {\begin{array}{*{20}{c}}
{x,\,\,\,\,\,\,x \in Q}\\
{0,\,\,\,\,\,\,x \notin Q}
\end{array}} \right.;g(x) = \left\{ {\begin{array}{*{20}{c}}
{x,\,\,\,\,\,\,x \in Q}\\
{0,\,\,\,\,\,\,x \notin Q}
\end{array}} \right.$ then function $(f -g)$ is :-
  • One-one onto
  • B
    One-one but not onto
  • C
    Onto but not one-one
  • D
    Neither one-one nor onto

Answer

Correct option: A.
One-one onto
a

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