焦点 4y^2-x^2=900

解答

焦点

4 y^{2} - x^{2} = 900

(0, 155), (0, - 155)

求解步骤

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

计算双曲线性质

4 y^{2} - x^{2} = 900 :

上下开口双曲线，

(h, k) = (0, 0), a = 15, b = 30

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

计算

c :

c = 1 5^{2} + 3 0^{2} : 155

(0, 0 + 155), (0, 0 - 155)

整理后得

(0, 155), (0, - 155)

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

f oc i \frac{x ^{2}}{64} - \frac{y ^{2}}{32} = 1

f oc i 25 y^{2} - 81 x^{2} = 2025

f oc i \frac{y ^{2}}{4} - \frac{x ^{2}}{16} = 1

f oc i \frac{( y + 3 ) ^{2}}{64} - \frac{( x + 6 ) ^{2}}{49} = 1