### 11.6.6 Find the points of intersection of two geometric objects
in the plane: inter

See section 12.4.4 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:

inter(circle(0,1),line(1,i))

draws the points at (1,0) and (0,1).
To get just one of the points, use the usual list indices.

Input:

inter(circle(0,1),line(1,i))[0]

draws just one of the points.
To get the point closest to (0,1/2), enter

Input:

inter(circle(0,1),line(1,i),i/2)