The inverse of the function \(f\left( x \right) = \frac{{{{10}^x} - {{10}^{ - x}}}}{{{{10}^x} + {{10}^{ - x}}}}\) is,
1
\({\log _{10}}\left( {\frac{{1 + x}}{{1 - x}}} \right)\)
2
\(\frac{1}{2}{\log _{10}}\left( {\frac{{1 + x}}{{1 - x}}} \right)\)
3
log10(1 + x)
4
\( - {\log _{10}}\left( {\frac{{1 + x}}{{1 - x}}} \right)\)