The equation of the sphere of the first divination limit is ∑ 2: z = √ (1-x 2-y 2), and its projection area on the xoy plane is x 2+y 2 ≤ 1, x≥0, y≥0.

But in the eighth gossip limit, X is positive, Y is negative and Z is negative, so the spherical equation is ∑ 1: z =-√ (1-X 2-Y 2), and its projection area on the xoy plane is X 2+Y 2 ≤ 1, and x≥0, y.

These two projection areas are different.