How to plot the following function using Tikz

Question

I am new to LaTeX and I want to know how to plot the following function using TikZ:

y = 300 + 1000/x + 2.5x.

at the interval 0:250

Answer 1

Here is a version adapted from Easiest way to plot a function with PGF/TikZ.

One does not need to use \pgfmathdeclarefunction, but I find it easier to maintian code if each function is declared as such.

Code:

\documentclass{article}
\usepackage{pgfplots}% This uses tikz
\pgfplotsset{compat=newest}% use newest version
\pgfmathdeclarefunction{Function}{1}{%
  \pgfmathparse{300 + 1000/x + 2.5}%
}
\tikzset{My Line Style/.style={smooth, ultra thick, samples=400}}
\begin{document}
\begin{tikzpicture}
\begin{axis}[unbounded coords=discard]
    \addplot[My Line Style, color=blue, domain=0:250] (\x,{Function(\x)});
\end{axis}
\end{tikzpicture}
\end{document}
\documentclass{article}