Let $f : R \rightarrow R$ be defined by $f ( x ) = \frac { | x | - 1 } { | x | + 1 }$, then $f$ is (1) one-one but not onto (2) neither one-one nor onto (3) both one-one and onto (4) onto but not one-one
Let $f : R \rightarrow R$ be defined by $f ( x ) = \frac { | x | - 1 } { | x | + 1 }$, then $f$ is\\
(1) one-one but not onto\\
(2) neither one-one nor onto\\
(3) both one-one and onto\\
(4) onto but not one-one