双曲线方程是[x^2/9-k]+[y^2/k-3]=1
[x^2/9-k]-[y^2/3-k]=1or[y^2/k-3]-[x^2/k-9]=1
一楼的过程,c=1,
12-2k=1or2k-12=1
k=11/2(3-k应该大于0,舍了) or13/2
所以k=13/2
双曲线方程是[x^2/9-k]+[y^2/k-3]=1
[x^2/9-k]-[y^2/3-k]=1or[y^2/k-3]-[x^2/k-9]=1
一楼的过程,c=1,
12-2k=1or2k-12=1
k=11/2(3-k应该大于0,舍了) or13/2
所以k=13/2