with(plots):
macro(palegreen=COLOR(RGB, .7, .9, .7),paleyellow=COLOR(RGB,.9,.9,.6));
f:=(x,y) -> 4*x^3-6*x*y^2+y^2;
p1:=plot3d(f(x,y),x=-4..4, y=-4..4, axes=boxed, style=patchnogrid):
p2:=implicitplot3d((x-3)^2+(y-2)^2+(z-f(3,2))^2=.01, x=2.9..3.1, y=1.9..2.1, z=f(3,2)-.1..f(3,2)+.1, color=black):
display(p1,p2);
p3:=contourplot(f(x,y),x=-4..4, y=-4..4, coloring=[blue,red], contours=40):
p5:=implicitplot((x-3)^2+(y-2)^2=.0049, x=2.93..3.07, y=1.93..2.07, color=black, thickness=3):
display(p3,p5);