Question

1. define eccentricity:

Explanation:

In mathematics, especially in conic - sections (ellipses, hyperbolas, parabolas), eccentricity is a measure of how much the conic - section deviates from being circular. For an ellipse, it is the ratio of the distance between the foci and the length of the major axis, and it is between 0 and 1. For a parabola, it is equal to 1. For a hyperbola, it is greater than 1.

Answer:

In mathematics, eccentricity is a measure that describes the deviation of a conic - section from being circular. For an ellipse, $01$, where $e$ is the eccentricity.