Let E1 E2 and F1 F2 be the chords of S passing through the point P0 (1,1) and parallel to the X-axis and the Y-axis, respectively. Let G1 G2 be the chord of S passing through P0 and having slope -1. Let the tangents to S at E1 and E2 meet at E3, then tangents to S at F1 and F2 meet at F3, and the tangents to S at G1 and G2 meet at G3. Then, the points E3, F3, and G3 lie on the curve