The function $f : (-\infty, \infty) \rightarrow (-\infty, 1)$, defined by $f(x) = \frac{2^{x} - 2^{-x}}{2^{x} + 2^{-x}}$ is: (1) Neither one-one nor onto (2) Onto but not one-one (3) Both one-one and onto (4) One-one but not onto
The function $f : (-\infty, \infty) \rightarrow (-\infty, 1)$, defined by $f(x) = \frac{2^{x} - 2^{-x}}{2^{x} + 2^{-x}}$ is:\\
(1) Neither one-one nor onto\\
(2) Onto but not one-one\\
(3) Both one-one and onto\\
(4) One-one but not onto