See section 13.4.4 for points of intersection of objects in space.
The inter command takes two geometric objects as arguments and returns a list of the points of intersection of the two objects.
The inter command optionally takes a point as a third argument. In this case, inter returns the point of intersection closest to this argument.
For example, entering
Input:
draws the points at (1,0) and (0,1).
To get just one of the points, use the usual list indices.
Input:
draws just one of the points.
To get the point closest to (0,1/2), enter
Input: