谁能提供几套英文的数学试题啊？

Problem 1
Consider the quadratic equation
x2 + y2 + Dx + Ey + F = 0:
What condition on the values of D, E and F determines whether this a circle?
Use this condition to show that
x2 + y2 ¡ 2x ¡ 4y + 3 = 0
is a circle and sketch the circle.
Does the point (0:4; 3) lie inside, outside or on this circle? Give a reason for
your answer.
Problem 2
Find the standard algebraic form of the equation of an ellipse with one focus at
(4; 0), directrix x = 9 and eccentricity 2/3. Is there another ellipse with these
properties? If so, ¯nd its equation. Sketch the ellipse(s).
Problem 3
The Earth orbits the Sun elliptically with the Sun as one focus. The major axis
is 1:86 £ 108 miles and the eccentricity is 0.0167. Find the smallest and largest
distances of the Earth from the Sun.
Problem 4
An elliptical snooker table is constructed without pockets. A ball is placed at o