MCQ
Which of the following is true 
  • If number of elements in set $A$ are finite, such that $f : A \to A$ is an one-one function, then $f$ is necessarily onto
  • B
    If a function is continuous in its domain and changes its sign for any $2$ values of $x$ then odd number of roots lie between the given values of $x$
  • C
    If $f : A \to A$ is one-one then it must be onto
  • D
    It is possible that a curve contains a local maxima and a global minima at the same point

Answer

Correct option: A.
If number of elements in set $A$ are finite, such that $f : A \to A$ is an one-one function, then $f$ is necessarily onto
a

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