焦点 (y^2)/(16)-(x^2)/(20)=1

解答

焦点

\frac{y ^{2}}{16} - \frac{x ^{2}}{20} = 1

(0, 6), (0, - 6)

求解步骤

(h, k + c), (h, k - c)

计算双曲线性质

\frac{y ^{2}}{16} - \frac{x ^{2}}{20} = 1 :

上下开口双曲线，

(h, k) = (0, 0), a = 4, b = 25

(0, 0 + c), (0, 0 - c)

计算

c :

c = 4^{2} + (25)^{2} : 6

(0, 0 + 6), (0, 0 - 6)

整理后得

(0, 6), (0, - 6)