To view level curves in Maple:

1. Execute a plot command like: plot3d(x^2+y^2,x=-2..2,y=-2..2,color=x^2+y^2,scaling=constrained,style=patchcontour,axes=boxed);
2. Click on the plot and rotate 135 degrees right (about z-axis) and 45 degrees down (about x-axis) to get a top view.

Comments:

• The coloring, scaling, style and axes may be omitted from the plot command and selected from menus that appear when the graphic is selected.
• Exact z values for the level curves can be indicated by using the contour option. For example, include contour = [0,1,2] in the plot command to restrict level curves to z=0, z=1, and z=2.
• Because Mathematica does not allow live manipulation of graphic objects, it is not suitable for this demonstration.
• The rotations can be automated via an animation.