Consider the ellipse a2x2+b2y2=1, where a>b>0.
(i) State the algebraic condition that a point P(x1,y1) must satisfy in order to lie (A) on the ellipse, (B) inside the ellipse and (C) outside the ellipse.
(ii) Explain, without performing any numerical calculation, how the sign of the expression a2x12+b2y12−1 determines the exact position of the point with respect to the ellipse.