source("http://macosa.dima.unige.it/r.R")
HF=2; BF=6
x1=-5*pi/2; x2=5*pi/2; y1=-1.1; y2=1.1
TICKx=pi/4; TICKy=1/2; Plane2(x1,x2, y1,y2)
f <- function(x) cos(x); g <- function(x) cos(2*x)
graph(f,x1,x2, "blue"); graph(g,x1,x2, "red")
graph1(f,x1,x2, "blue")
underX( bquote(2*pi),2*pi); underX( bquote(-2*pi),-2*pi)
underX( bquote(pi),pi); underX( bquote(-pi),-pi)
underX(0,0)
underY(0,0); underY(1,1); underY(-1,-1)