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Factorisation de polynômes de degré supérieur

Saisie du polynôme

Exemples de polynômes :

Instructions de format :

Notation exposant : Utilisez le symbole ^, ex. x^2, x^3
Notation multiplication : Utilisez le symbole *, ex. 2*x^2, -3*x
Addition et soustraction : Utilisez + et - pour relier les termes
Terme constant : Entrez directement les nombres, comme +6, -12

Résultat de la factorisation

Saisissez le polynôme et cliquez sur Lancer

Explication de l'algorithme :

1. Théorème des racines rationnelles :
For an integer-coefficient polynomial a_n·x^n + ... + a_1·x + a_0, if there exists a rational root p/q (in simplest form), then:
  • p must be a factor of the constant term a_0
  • q must be a factor of the leading coefficient a_n
  • Possible rational roots are: ±(factors of p) / (factors of q)
  • Example:For x³ - 6x² + 11x - 6, possible rational roots are ±1, ±2, ±3, ±6
2. Division synthétique :
Used to verify roots and perform polynomial division:
  • If r is a root of polynomial P(x), then P(x) = (x - r)·Q(x)
  • Synthetic division quickly finds the quotient polynomial Q(x)
  • Continue factoring Q(x) until it can no longer be factored
3. Méthodes numériques de recherche de racines :
When the Rational Root Theorem fails to find integer roots, use numerical methods:
  • Newton's Iteration Method:x_{n+1} = x_n - f(x_n)/f'(x_n)
  • Used to find real roots (which may be irrational)
  • For complex roots, display the real and imaginary parts
  • Example:x^2 - 2 = (x - sqrt(2))(x + sqrt(2))
4. Reconnaissance de formes spéciales :
  • Difference of Squares:a^2 - b^2 = (a + b)(a - b)
  • Perfect Square:a^2 +/- 2ab + b^2 = (a +/- b)^2
  • Difference/Sum of Cubes:a^3 +/- b^3 = (a +/- b)(a^2 -/+ ab + b^2)
  • Extract Common Factors:For example, x³ + 2x² = x²(x + 2)

Complexité algorithmique :

  • Rational Root Search:O(d·n), where d is the number of possible roots and n is the polynomial degree
  • Synthetic Division:O(n) per division
  • Numerical Root Finding:O(k·n), where k is the number of iterations

Remarques :

  • Only supports polynomials with integer coefficients
  • For higher-degree polynomials (degree ≥ 5), complete factorization into rational roots may not be possible
  • Numerical solutions may have rounding errors and are displayed as approximate values
  • Complex roots are displayed in the form a + bi
  • Irreducible polynomials will be displayed in their original form