The formula of the chord length of an ellipse is d = √ (1+k2) * | x1-x2 | = √ {(1+k2) * [(x1+x2) 2-4 * x1. Elliptic chord length formula is a mathematical formula. The general method to find the chord length when a straight line intersects a conic curve is to substitute the straight line y=kx+b into the curve equation and turn it into a quadratic equation about x (or about y).

Explanation of the origin of ellipse

In the eight-volume book "Quadric Curve on Quadric Curve" by Apollonius, well-known terms such as ellipse, parabola, hyperbola and hyperbola were put forward for the first time, which can be said to be a masterpiece of ancient Greek geometry. It was not until the turn of the sixteenth and seventeenth centuries that Kepler's three laws of planetary motion were discovered, and the orbit of the planet around the sun was an ellipse with the sun as the focus.