Quadratic

In mathematics, the term quadratic describes something that pertains to squares, to the operation of squaring, to terms of the second degree, or equations or formulas that involve such terms. Quadratus is Latin for square.

Mathematics

Algebra (elementary and abstract)

Quadratic function (or quadratic polynomial), a polynomial function that contains terms of at most second degree
- Complex quadratic polynomials, are particularly interesting for their sometimes chaotic properties under iteration
Quadratic equation, a polynomial equation of degree 2 (reducible to 0 = ax² + bx + c)
Quadratic formula, calculation to solve a quadratic equation for the independent variable (x)
Quadratic field, an algebraic number field of degree two over the field of rational numbers
Quadratic irrational or "quadratic surd", an irrational number that is a root of a quadratic polynomial

Calculus

Quadratic integral, the integral of the reciprocal of a second-degree polynomial

Statistics and stochastics

Quadratic form (statistics), scalar quantity ε'Λε for a n-dimensional square matrix
Quadratic mean, the square root of the mean of the squares of the data
Quadratic variation, in stochastics, useful for the analysis of Brownian motion and martingales

Number theory

Quadratic reciprocity, a theorem from number theory
Quadratic residue, an integer that is a square modulo n
Quadratic sieve, a modern integer factorization algorithm

Other mathematics

Quadratic convergence, in which the distance to a convergent sequence's limit is squared at each step
Quadratic differential, a form on a Riemann surface that locally looks like the square of an abelian differential
Quadratic form, a homogeneous polynomial of degree two in a number of variables
Quadratic programming, a special type of mathematical optimization problem
Quadratic growth, an asymptotic growth rate proportional to a quadratic function
Periodic points of complex quadratic mappings, a type of graph that can be used to explore stability in control systems
Quadratic bézier curve, a type of bezier curve

Computer science

Quadratic probing, a scheme in computer programming for resolving collisions in hash tables
Quadratic classifier, used in machine learning to separate measurements of two or more classes of objects
Quadratic time, in referring to algorithms with quadratic time complexity

Other

Quadratic (collection), a 1953 collection of science fiction novels by Olaf Stapledon and Murray Leinster