For the following two (02) items:
Consider the function  $f(x)=\frac{10^{x}-10^{-x}}{10^{x}+10^{-x}}$

What is$f\circ f\circ f\circ f\circ f(0)$ equal to?

For the following two (02) items:
Consider the function  $f(x)=\frac{10^{x}-10^{-x}}{10^{x}+10^{-x}}$

What is the inverse of the function?

What is the degree of the differential equation
$(\frac{d^{2}y}{dx^{2}})^{\frac{3}{2}}=(\frac{dy}{dx})^{\frac{5}{2}}$

What is $\int _{n}^{n+1}(x-[x])dx$, where [.] is the greatest integer function and n is natural number?