I am attempting to find the surface area of a Torus. I can create a graph very easily, but am struggling with the SurfaceArea command. The code reads so far:

(Inputting the given function for the torus):

> r := (phi,theta) -> <(cos(phi)+3)*cos(theta),(cos(phi)+3)*sin(theta),sin(phi)>:

'r(phi,theta)' = r(phi,theta); 

(Generating a graph of the torus):

>plot3d(r(phi,theta),phi=0..2*Pi,theta=0..2*Pi,scaling=constrained);

(SurfaceArea command):

>SurfaceArea(r(phi,theta),phi=0..2*pi,theta=0..2*pi);

I am very new to the program so the solution may be obvious. Any suggestions on how to go about it?

Hello, I am attempting to plot a vector field in Maple. I have the following code so far:

SetCoordinates('cartesian'[x,y,z]):

F := VectorField(<y*z*e^(x*y*z)+3*x^(2),x*z*e^(x*y*z)+2*y*z+cos(y),x*y*e^(x*y*z)+y^(2)+1>);

I am struggling with the fieldplot3d commands, as I am supposed to plot it in the box -1<=x,y,z<=1. How do I go about inserting these bounds?