how to plot f(x)=ax^2+bx+c with 5-point and line in the same fig



Hi again,

Try draw2d instead of plot2d.

(%i31) load(draw)$
(%i33) m:makelist([j,F(j)],j,i-2,i+2);
(%o33)                                     [[- 3, 11], [- 2, 5], [- 1, 3], [0, 5], [1, 11]]
(%i34) draw2d(point_type=circle, point_size = 2, color=red, points(m), color=blue, explicit(F(x),x,-10,10));
(%o34)                                                 [gr2d(points, explicit)

Rich