If e1 and e2 are the eccentricity of hyperbola x2a2−y2b2=1 and y2a2−x2b2=1 , then point 1e1,1e2 lies on the circle.
We already discussed the property
e−21+e−22=1 in a given hyperbola and its conjugate hyperbola.
This is a different way of asking the same property.
Since (x,y)=(e−21+e−22=1)
x2+y2=1 will be circle on which the point would always fall due to the property.