Download maple_plot3d.mw, click here!

> f:=x^2/(x^2+y^2);
 

x^2/(x^2+y^2) 

> plot3d(f,x=-4..4,y=-4..4,axes=BOXED);
 

Plot 

> f:=sin(x+y)/(x+y);
 

sin(x+y)/(x+y) 

> plot3d(f,x=-10..10,y=-10..10,axes=BOXED);
 

Plot 

> f:=x^2+y^2;
 

x^2+y^2 

> plot3d(f,x=-4..4,y=-4..4,axes=BOXED);
 

Plot 

> f:=x^3+y^2;
 

x^3+y^2 

> plot3d(f,x=-4..4,y=-8..8,axes=BOXED);
 

Plot 

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