MCQ
If $f:R \to R$, then $f(x) = \;|x|$ is
  • A
    One-one but not onto
  • B
    Onto but not one-one
  • C
    One-one and onto
  • None of these

Answer

Correct option: D.
None of these
d
(d) $f( - 1) = f(1) = 1$;

$\therefore $function is many-one function.

Obviously, $f$ is not onto so $ f$ is neither one-one nor onto.

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