The function $f(x,y)$ satisfies the Laplace equation $$\bigtriangledown^{2}f(x,y) = 0$$
on a circular domain of radius $r=1$ with its center at point $P$ with coordinates
$x=0, y=0.$ The value of this function on the circular boundary of this domain
is equal to $3.$
The numerical value of $f(0,0)$ is:
- $0$
- $2$
- $3$
- $1$