1.C = 5, A 2 = B 2+C 2 is substituted into the ellipse and asymptotic formula, and it comes out. 2. Let x 2+2y = k x 2 = k-2y. Substitute it into the ellipse. -there is a root 3 between b, b and b. I forgot this concept. 4. Write the equation AF 1, and find out A.5, the smallest vertical X axis, 2p. Definition of cause parabola 6. Let p coordinate, (y 2/4, y) find PQ, and take A as the interval where the equation has a solution. 7. Set equations instead of formulas. 8. Just saying. 9. Set equations instead of formulas.