两圆x²+y²+2ax+2ay+2a²-1=0与x²+y²+2bx+2by+2b²-2=0的公共弦长的最大值是

两圆x²+y²+2ax+2ay+2a²-1=0与x²+y²+2bx+2by+2b²-2=0的公共弦长的最大值是
两圆x²+y²+2ax+2ay+2a²-1=0与x²+y²+2bx+2by+2b²-2=0的公共弦长的最大值是

两圆x²+y²+2ax+2ay+2a²-1=0与x²+y²+2bx+2by+2b²-2=0的公共弦长的最大值是
x^2+y^2+3x-y=0(1)
3x^2+3y^2+8x+y=0(2)
(1)*3 3x^2+3y^2+9x-3y=0(3)
(3)-(2) x-4y=0
x=4y(4)
(4y)^2+y^2+12y-y=0
16y^2+y^2+11y=0
17y^2+11y=0
y(17y+11)=0
y1=0,y2=-11/17
x1=0,x2=-44/17
A(0,0),B(-44/17,-11/17)
AB^2=(44^2/17^2+11^2/17^2)=2057/17^2
AB=2057^1/2/17
公共弦长AB=2057^1/2/17