Claudius,
> excuse me if this is a silly question, but I'm a new to maxima.
No problem. Thanks for your interest in Maxima.
> I want to plot a lot of functions with one line. There are functions like
> f(x,t) = t*x + 2, x in R, t in [0,1,2,3,4,5,6,7]
The plot2d function can accept multiple expressions as a list.
Try this:
f(x,t) := t*x + 2;
makelist (f(x, t), t, 0, 7);
plot2d (%, [x, -10, 10]);
Hope this helps
Robert Dodier