x^2/4+y^2=1
a^2=4,b^2=1,c^2=4-1=3
故双曲线的左右焦点坐标是F1(-2,0),F2(2,0),左右顶点分别是(-根号3,0)和(根号3,0)
即有c=2,a=根号3,b^2=4-3=1
故C2方程是x^2/3-y^2=1
x^2/4+y^2=1
a^2=4,b^2=1,c^2=4-1=3
故双曲线的左右焦点坐标是F1(-2,0),F2(2,0),左右顶点分别是(-根号3,0)和(根号3,0)
即有c=2,a=根号3,b^2=4-3=1
故C2方程是x^2/3-y^2=1