Find the minimum value of △ABE area, that is, the maximum value of △BEO area.
It can be seen that when BD is tangent to circle C and above the X axis, the area of △BEO is the largest.
Because BC=3, CD= 1.
So the root number 2 of DB=2
Let D(x, y)
With BD squared =(y-0)? +(x-2)? =8
CD? =(y-0)? +(x+ 1)? = 1
Simultaneous two forms, x=-2/3, y=2 root 2/3.
Then the straight BD equation is y=- root number 2x/4+ root number 2/2.
So the coordinates of point E are (0, root number 2/2).
So △ Abe area =△ Abe area -△BEO area.
=2*2/2-2* Root number 2/2/2
The root number of =2 is 2/2