%Gilles Mora 40 setxunit 7.5 setborder 90 setangle_repere -4 4.5 setxrange -3 5 setyrange 1 1 settkstep .5 .5 setsubtkstep 2 2 setmkstep ticks subticks marks traceaxes axesarrow %unites /f {setxvar #rpn# x+1+2/(x-5) } def /g {setxvar #rpn# x+1 } def gsave noir .75 setlinewidth continu {f} courbe grestore gsave noir .75 setlinewidth continu {g} courbe grestore $y=ax+b$ boxit 2.1 5 [1.5 dup] dctexlabel $C_f$ boxit 3.8 2 [1.5 dup] dctexlabel