Question: I have little problem with 3D plot in Maple

Hi peoples,I have little problem with 3D  plot in Maple

I am build my function in this way:

mu1(x,y) := (100e6*Transpose(Vector([300,0]))*(Vector([-10,-10])-Vector([x,y])))/(VectorNorm(Vector([-10,-10])-Vector([x,y]),2)*3e8);

mu3(x,y) := (100e6*Transpose(Vector([300,0]))*(Vector([10010,10010])-Vector([x,y])))/(VectorNorm(Vector([10010,10010])-Vector([x,y]),2)*3e8);

mu2(x,y) := (100e6*Transpose(Vector([300,0]))*(Vector([10010,-10])-Vector([x,y])))/(VectorNorm(Vector([10010,-10])-Vector([x,y]),2)*3e8);

costf(x,y) :=(2*775.6-870.67-897.06+(mu2+mu3-2 *mu1)^2) +(2*870.67-775.6-897.06+(mu1+mu3-2 *mu2)^2)+ (2*897.06-775.6-870.67+(mu1+mu2-2* mu2)^2);

plot3d(costf(x, y), x = 0 .. 10000, y = 0 .. 10000);

here I receive error masage:

Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct

In addition, How I can send all constants that exist here (besides x and y) from Matlab.