If the focus of the ellipse x ^ 2 / 25 + y ^ 2 / M = 1 is on the x-axis and the ratio of the focal length to the length of the major axis is 1:3, then M

If the focus of the ellipse x ^ 2 / 25 + y ^ 2 / M = 1 is on the x-axis and the ratio of the focal length to the length of the major axis is 1:3, then M


The focus is on the X axis
So m



If the focal length of the ellipse with focus on X axis X ^ 2 / M + y ^ 2 / 4 = 1 is equal to 2, then M =? Find the specific process,


The focus is on the X axis
m=a²,4=b²
c²=m-4
The focal length is 2C = 2
c=1
So m = 5



Given that the focus of the ellipse X & # 178; + KY & # 178; = 1 is on the x-axis, and the length of the major axis is three times that of the minor axis, then the value of the real number k is


x²+ky²=1
x²+y²/(1/k)=1
The focus is on the X axis
Then a = 1, B = 1 / √ K
The length of the long axis is three times that of the short axis
That is, 2A = 3 * (2b)
a=3b
That is, 1 = 3 / √ K
So k = 9



If the line y-kx-1 = 0 and the ellipse x ^ 2 / 5 + y ^ 2 / M = 1 have a common point, then the range of M is?
No, the answer is - 1 to 1 or negative root 2


Combination of number and shape: straight line passing through point (0,1)
1. If M 〉 = 1, the point (0,1) is in the ellipse, so there is always an intersection. But let x ^ 2 / 5 + y ^ 2 / M = 1 be an ellipse, so m! = 5, so m belongs to [1,5] and (5, positive infinity)
2. If M0, let the equation have a unique solution, then 5K ^ 2 = 1-m > 0, then M