How to do the problem of Chongqing 20 14 college entrance examination science mathematics volume 2 1? Is it the finale of college entrance examination? It's a little difficult, conic or something, dizzy This topic examines the synthesis of straight lines and conic curves, the idea of reduction, the classification of equation ideas, the comprehensive application of ideas, and the comprehensive analysis and calculation ability, which are all difficult problems. See /exercise/math/804606 for the answer.

As shown in the figure, let the ellipse x2/a2+y2/B2 =1(a >; B>0) The left and right focal points are F 1 and F2, respectively, and the point D is on the ellipse. DF 1 area perpendicular to F 1F2, | f1F2 | | df1| = 2 times the root number 2, and the area of △ Df 1F2 is (root

(1) Find the standard equation of ellipse;

(2) Let the circle with the center on the Y-axis and the ellipse have two intersections above the X-axis, and the two tangents of the circle at these two intersections are perpendicular to each other, and the radius of the circle is calculated through different focal points.