Implicit plotting with JSXGraph

Examples:
x**2 - 6*x + y**2 - 4*y + 13 x^2+y^2+x*y*2-2 x^2 + y^2 + 2*x*y sin(PI*(x**2 + y)) + cos(PI*y) 1 / 9 * x ** 2 + y ** 2 - 1
Constraints:
-x^2-y+1 x^2+y-1 -y+1 y-0.1 y-0.001 4*(x-7)**2 + 4*(y-4)**2 - 5 -x+y x + y - 2 x^2 + y^2 + 2*x*y 1 / 16 * x ** 2 + y ** 2 - 1 x

Equation:
0 = select
0 = select
Kontourlinien
set