Written by the Fiveable Content Team โข Last updated September 2025
Written by the Fiveable Content Team โข Last updated September 2025
Definition
An elliptic integral is an integral involving a square root of a polynomial of degree 3 or 4. These integrals cannot generally be expressed in terms of elementary functions.
5 Must Know Facts For Your Next Test
Elliptic integrals are categorized into three types: the first kind, the second kind, and the third kind.
The incomplete elliptic integral of the first kind is denoted as $F(\phi, k)$ and involves parameters $\phi$ (amplitude) and $k$ (modulus).
The complete elliptic integral of the first kind is denoted as $K(k)$ and does not depend on $\phi$. It is defined as $K(k) = F(\frac{\pi}{2}, k)$.
Applications of elliptic integrals include calculating arc lengths of ellipses and solving Keplerโs problem in celestial mechanics.
Elliptic integrals can be approximated using Taylor series expansions for small values of the modulus $k$.