Polynomial
A polynomial is a linear combination of powers of a variable (e.g., ax²+bx+c), supporting addition, subtraction, multiplication, division, differentiation, and integration; it is the foundation of algebra and numerical computing.
Purpose
To represent and manipulate algebraic expressions, the basis of interpolation, approximation, and equation solving.
Mechanism
P(x)=a_n×x^n+...+a_1×x+a_0. The degree is the highest power. Addition and subtraction work coefficient-wise; multiplication convolves coefficients. Evaluation uses Horner's method in O(n). Root finding: closed formulas for low degrees, Newton iteration for high degrees. FFT accelerates polynomial multiplication to O(n log n).
Use cases
- Curve fitting and interpolation
- Error-correcting codes (Reed-Solomon)
- CRC generator polynomials
- Numerical approximation
Examples
- Input
2x²+3x+1 at x=2Output2×4+3×2+1=15Horner evaluation
Common errors
- High-degree polynomials are numerically unstable
- Use orthogonal polynomials or center the variable
Related terms
Matrix
A matrix is a rectangular array of numbers supporting addition, subtraction, multiplication, transposition, and inversion; it is the foundation of linear algebra and computer graphics. GLOSSARY
Complex Number
A complex number has the form a+bi (i²=-1), extending the reals to two dimensions; it underpins signal processing and quantum computing. GLOSSARY
BigInteger
BigInteger is an arbitrary-precision integer type, not limited by a fixed word size, used for computations beyond the native integer range (such as cryptography and combinatorics). GLOSSARY