[tex]f(x)=-\log(x-4)\\\\\text{The domain:}\\x-4 > 0\to x > 4\to x\in(4;\ \infty)[/tex]
[tex]\text{The range of}\ y=\log x\ \text{is}\ \mathbb{R},\\ \text{and the range of}\ y=-\log x\ \text{is}\ \mathbb{R}\\\text{and the range of }\ f(x)=-\log(x-4)\ \text{is}\ \mathbb{R}[/tex]
