Let the right focus of the ellipse be, the straight lines intersect at two points, and the coordinates of the points are.

(i) When perpendicular to the axis, find the equation of the straight line;

(ii) Set it as the coordinate origin and prove that:

Answer question one

The main parameters of an ellipse are:

The right focal coordinate is.

The straight line is perpendicular to the axis and passes through this point, and its equation is:, which can be obtained by substituting into the elliptic equation:

The equation for a straight line is:

Answer question Ⅱ

The equation of the straight line passing through this point is:, and the coordinates of two points satisfy the following equation:

After exclusion, you will get:

Prove it's over

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20 18 the first volume of the whole country got the equiangular problems in analytic geometry, mathematical numbers and literature numbers. The text volume is parabola; Ellipse of mathematical volume. The difficulty is not high, and it is suitable for the supplementary exercise of vieta theorem.