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The two ends of the minor axis of the ellipse form 120 degrees with the line connecting the focus, and the eccentricity of the ellipse is calculated
1/2
Because B / C = Tan 60 degrees = root 3,
a^2=b^2+c^2,
So e = C / a = 1 / 2
What is the eccentricity of the ellipse when the minor axis of the ellipse forms an angle of 120 ° with the line connecting the focus?
Let the focus be C, the vertex of the minor axis be B, and the origin be o
The line between the minor axis of the ellipse and the focus forms an angle of 120 degrees, that is, the angle between OB and 0C is 60 degrees
So, ob / OC = B / C = Tan 60 degree = √ 3
According to a ^ 2 = C ^ 2 + B ^ 2
The centrifugal ratio e = C / a = 1 / 2
Must assist graphics, very intuitive
End of solution
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