Major Axis and Minor Axis
Definition of Major Axis and Minor Axis
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Major Axis of an ellipse is the line passing through the foci, center, and vertices of of the ellipse.
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Minor Axis of an ellipse is the line through the center of the ellipse, which is perpendicular to the major axis.
Examples of Major Axis and Minor Axis
More about Major Axis and Minor Axis
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Major Axis of a hyperbola is the line passing through the foci, center, and vertices of the hyperbola.
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Minor Axis of a hyperbola is the line through the center of the hyperbola, which is perpendicular to the major axis.
- The major and minor axes of an ellipse are its axes of symmetry.
- The major and minor axes of a hyperbola are its axes of symmetry.
Solved Example on Major Axis and Minor Axis
Find an equation in standard form for the ellipse whose end points of axes are 
and 
.
Choices:
A. 
B. 
C. 
D. 
Correct Answer: A
Solution:
Step 1: End points of the axes of the ellipse are (- 9, 0), (9, 0), (0, - 10) and (0, 10).
Step 2: Distance between (- 9, 0) and (9, 0) is 
=18.
[Use distance formula.]
Step 3: Distance between (0, - 10) and (0, 10) is 
=20.
[Use distance formula.]
Step 4: So, the distance between (0, - 10) and (0, 10) is greater than the distance between (- 9, 0) and (9, 0).
Step 5: Hence, the focal axis of the ellipse is y - axis.
Step 6: So, semi-major axis = 
and semi-minor axis = 
.
Step 7: The equation of the ellipse in the standard form is 
.
Related Terms for Major Axis and Minor Axis
- Ellipse
- Hyperbola
- Axis of Symmetry
- Foci
- Center
- Vertices
- Perpendicular
Additional Links for Major Axis and Minor Axis
