Functions of two variables

Task

Graph the function f(x, y) = sin(x + y) and observe the created surface by moving a point along the function graph.

1.		Enter `f(x, y)= sin(x + y)` into the Input Bar and hit the Enter key to define a function f.
2.		Create the point A by entering `A = (2, 0, 0)` into the Input Bar and hitting the Enter key.
3.		Enter `Segment(A, (x(A), y(A), f(x(A), y(A))))` into the Input Bar to create a segment g.
4.		Create the point B by entering `B = (x(A), y(A), f(x(A), y(A)))` into the Input Bar.
5.		Exploration: Use the Move tool to change the position of point A. You can also change the function f by entering another function: e.g. `f(x, y)= sin(x) + sin(y)`
7.		Enhance your construction using the Style Bar.