Polynomial Calculator

Evaluate a polynomial at any value of x, add or subtract two polynomials, or multiply them. Enter coefficients from highest to lowest degree and get instant results with full simplification.

Polynomial Basics

P(x) = aₙxⁿ + aₙ₋₁xⁿ⁻¹ + ... + a₁x + a₀
Degree = highest power with non-zero coefficient
Example: 2x³ − 5x² + 3x − 7 (degree 3, 4 terms)

Polynomial Terminology

TermMeaningExample
MonomialOne term4x²
BinomialTwo termsx² − 9
TrinomialThree termsx² + 5x + 6
DegreeHighest exponentx³ → degree 3
Leading coefficientCoefficient of highest term3 in 3x⁴+...
Constant termTerm with no x−7 in 2x²−7

Frequently Asked Questions

How do I multiply two polynomials?

Use the distributive property: multiply every term of the first polynomial by every term of the second, then collect like terms. For (x+2)(x+3): x·x + x·3 + 2·x + 2·3 = x² + 3x + 2x + 6 = x² + 5x + 6. This calculator does this automatically for up to degree 5 polynomials.

What is the Remainder Theorem?

When a polynomial P(x) is divided by (x − a), the remainder equals P(a). So evaluating a polynomial at x = a (which this calculator does) is equivalent to finding the remainder of P(x) ÷ (x − a). If P(a) = 0, then (x − a) is a factor.

How do I find roots of a polynomial?

Roots are values of x where P(x) = 0. For degree 1: solve ax + b = 0. For degree 2: use the quadratic formula. For degree 3–4: use Cardano/Ferrari formulas or numerical methods. For degree 5+: no general algebraic formula exists (Abel–Ruffini theorem) — numerical methods like Newton's method are used.

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