Hi

I have a position P determined by the point, at which a vectorvpoints to. Now I have a function, which is only defined for the points on and inside a circle with radius 2 within P. Can I write this interval as

$\displaystyle

x,y \in (x-v_x)^2-(y-v_y)^2=4

$

?

Sincerely,

Niles.