焦点 y^2-(x^2)/4 =1

解答

焦点

y^{2} - \frac{x ^{2}}{4} = 1

(0, 5), (0, - 5)

求解步骤

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

计算双曲线性质

y^{2} - \frac{x ^{2}}{4} = 1 :

上下开口双曲线，

(h, k) = (0, 0), a = 1, b = 2

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

计算

c :

c = 1^{2} + 2^{2} : 5

(0, 0 + 5), (0, 0 - 5)

整理后得

(0, 5), (0, - 5)

f oc i - 9 x^{2} + 4 y^{2} - 36 x - 16 y - 164 = 0

f oc i \frac{( x + 5 ) ^{2}}{4} - \frac{y ^{2}}{4} = 1

f oc i - \frac{( x - 2 ) ^{2}}{9} + \frac{( y + 1 ) ^{2}}{5} = 1

f oc i - 25 x^{2} + 4 y^{2} + 150 x + 24 y - 289 = 0

f oc i 9 x^{2} - 16 y^{2} + 36 x + 32 y - 124 = 0