Question

Question #3cef9

Answer 1

The annular border-inclusive annular region
`2-pi/2 <=x^2+y^2<=2+pi/2` is the mapping of (x, y), for the range `[-pi/2, pi/2]`..

Explanation:

Use `arc cos a in [-pi/2, pi/2]`

Here, `a = x^2+y^2-2`.

Range is #[ -pi/2, pi/2}. The mapping of (x, y) for this range is upon

the annular region

`2-pi/2 <=x^2+y^2<=2+pi/2`

Graph is inserted.

graph{(x^2+y^2-3.57)(x^2+y^2-.43)=0 [-10, 10, -5, 5]}