If the function $f : R \to R$ is defined by $f(x) = log_a(x + \sqrt {x^2 +1} ), (a > 0, a \neq 1)$, then $f^{-1}(x)$ is
$\left( {\frac{{{a^x} + {a^{ - x}}}}{2}} \right)$
$\left( {\frac{{{a^x} - {a^{ - x}}}}{2}} \right)$
Doesn't exist $\forall x \in R$
Exists for $x \in R^+$ only
Consider $f: R \rightarrow R$ given by $f(x)=4 x+3 .$ Show that $f$ is invertible. Find the inverse of $f$
State with reason whether following functions have inverse $g :\{5,6,7,8\} \rightarrow\{1,2,3,4\}$ with $g=\{(5,4),(6,3),(7,4),(8,2)\}$
It is easy to see that $f$ is one-one and onto, so that $f$ is invertible with the inverse $f^{-1}$ of $f$ given by $f^{-1}=\{(1,2),(2,1),(3,1)\}=f$
Consider $f:\{1,2,3\} \rightarrow\{a, b, c\}$ given by $f(1)=a, \,f(2)=b$ and $f(3)=c .$ Find $f^{-1}$ and show that $\left(f^{-1}\right)^{-1}=f$.
If $a * b=10$ ab on $Q^{+}$ then find the inverse of 0.01