For the following two (02) items:
Consider the function
$f(x)=\frac{x}{1-x}(x>0,x\ne 1)$

What is $\frac{f(x)}{f(x+1)}$ equal to?

For the following two (02) items:
Consider the function
$f(x)=\frac{x}{1-x}(x>0,x\ne 1)$

What is $ (1-x)f(\sqrt{x})+xf(\sqrt{x}+1)$ equal to?
 

For the following two (02) items:
Consider the function $f(x)=1-\sqrt[3]{(x-1)^{2}}$

What is the domain of the function?

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?