B
[-1,8)
k=1 2 3 y=2x^2+4x-6 (-1/2,3/2)
(1,-4)(3,0)(-1,0) m=1 or 13/4 [2/3,1)
m=0 or 4 y=x^2-2x-8 b=-8 or -41/4
PC=2 (-2,0]or(2,4]
y=根3/3 x+2 菱形 (-根3-根2/2,根6/2)
[-1,8)
k=1 2 3 y=2x^2+4x-6 (-1/2,3/2)
(1,-4)(3,0)(-1,0) m=1 or 13/4 [2/3,1)
m=0 or 4 y=x^2-2x-8 b=-8 or -41/4
PC=2 (-2,0]or(2,4]
y=根3/3 x+2 菱形 (-根3-根2/2,根6/2)
