1: The simplified straight line is the right directrix, and it is easy to get C = 4 and A = 6 after simplification.
2. Let E F be (x, y) (-x, 4-y) P(a, b) respectively.
PE*PF=(x-a，y-b)*(-x-a，4-y-b)
= a 2-x 2+4y-4b-y 2+b 2 Next, we get the elimination from the analytic formula of the circle: x 2+y 2 = 4y-3.
=a^2+b^2-(4y-3)+4y-4b
= a 2+b 2-4b+3 Next, use the elliptic analytical formula to solve the elimination: a 2 = 6-3b 2.
The value of =-2b 2-4b+9b is-root 2 to root 2. Let's go to one yuan and get the maximum twice.
B=- 1 to get the maximum value, and substitute it to get 1 1.