원과 접선(tangent line) (1)
\begin{tikzpicture} [+preamble] \usepackage{pgfplots} \pgfplotsset{compat=newest} [/preamble] \begin{axis}[xlabel=$x$,ylabel=$y$,axis lines=middle, axis line style={gray!30,latex-latex},xtick={1},ytick={1}, no marks,axis equal,xmin=-1,xmax=2,ymax=1.5,ymin=-1,enlargelimits={upper=0.1} ] \draw[thin,gray!30] (1,0) |- (0,1);…