12/02/25 23:15:40.48 J+HmgTme0
>>239
(x+ay)^2+(ax+2y)^2=1
(1+a^2)x^2+6axy+(a^2+4)y^2=1
a=0
ax+2y=p(x+ay)+q
(a-p)x+(2-ap)y=q
(x,y)=(±1,0),(0,±1/2)
q=0,a=p=±√2
X=x±y√2
(X±y√2)^2+4y^2=1
6y^2±2Xy√2+(X^2-1)=0
2X^2-6(X^2-1)≧0
6≧4X^2
-√(3/2)≦X≦√(3/2)
12/02/25 23:15:40.48 J+HmgTme0
>>239
(x+ay)^2+(ax+2y)^2=1
(1+a^2)x^2+6axy+(a^2+4)y^2=1
a=0
ax+2y=p(x+ay)+q
(a-p)x+(2-ap)y=q
(x,y)=(±1,0),(0,±1/2)
q=0,a=p=±√2
X=x±y√2
(X±y√2)^2+4y^2=1
6y^2±2Xy√2+(X^2-1)=0
2X^2-6(X^2-1)≧0
6≧4X^2
-√(3/2)≦X≦√(3/2)