Name: polynomial graphs, zeros, and degree
Uploaded: 2025-11-26T05:43:59.000Z
Duration: 1 min 26 s
Channel: JoVE

Un ballon de football botté suit une trajectoire courbe, qui peut être modélisée par un polynôme quadratique.Les fonctions polynomiales combinent des constantes et des variables en utilisant l’addition, la soustraction ou la multiplication, avec des variables élevées à des puissances entières non négatives.Le terme avec l’exposant le plus élevé est le terme principal, et son coefficient est le coefficient principal.Les polynômes sont classés par leur degré, qui est le terme dont la variable a la puissance la plus élevée.Les graphes polynomiaux sont lisses et continus. Le graphe d’un polynôme de degré 1 est une droite, le degré 2 forme une courbe en forme de U, et les degrés supérieurs produisent des graphes plus courbés avec plus de points de retournement possibles.Les graphes de polynômes de degrés impairs s’étirent dans des directions opposées, tandis que les graphes de degrés pairs s’étirent dans la même direction.Un zéro d’un polynôme est une valeur x où la fonction est égale à zéro et le graphique touche ou croise l’axe des x.Une fonction linéaire, un exemple typique d’un polynôme, suit le théorème des valeurs intermédiaires. Ce théorème stipule que si la fonction est continue et que son résultat est positif en un point et négatif en un autre, alors son graphique doit traverser l’axe des x entre eux.

fonctions polynomiales et leurs graphes

Les fonctions polynomiales constituent des &#233;l&#233;ments fondamentaux de l&#8217;alg&#232;bre et de l&#8217;analyse. Elles sont d&#233;finies par des expressions qui combinent des variables et des constantes au moyen d&#8217;additions, de soustractions et de multiplications, la variable &#233;tant &#233;lev&#233;e &#224; des exposants entiers positifs ou nuls. Une fonction polynomiale g&#233;n&#233;rale de degr&#233; n s&#8217;&#233;crit comme suit&#160;:<figure class='image image-style-align-center image_resized' style='display:table;margin-left:auto;margin-right:auto;width:75%;'><img style='aspect-ratio:1223/87;' src='https://cloudfront.jove.com/files/ftp_upload/40054/40054_Equation_1_editor_40054.svg' alt='40054_Equation_1.svg' /></figure>o&#249; a_n &#8800; 0. Le terme a_n x_n est appel&#233; terme dominant et a_n, coefficient dominant, tandis que a_0 est le terme constant.Caract&#233;ristiques et classificationLes polyn&#244;mes sont class&#233;s selon leur degr&#233;. Un polyn&#244;me de degr&#233; z&#233;ro correspond &#224; une fonction constante, les fonctions lin&#233;aires sont de degr&#233; un, les fonctions quadratiques sont de degr&#233; deux, et ainsi de suite. Le degr&#233; d&#233;termine le nombre maximal de points de retournement et influence la forme g&#233;n&#233;rale du graphe. Les polyn&#244;mes de degr&#233; impair s&#8217;&#233;tendent dans des directions oppos&#233;es lorsque x &#8594; &#177;&#8734;, tandis que les polyn&#244;mes de degr&#233; pair s&#8217;&#233;tendent dans la m&#234;me direction.Caract&#233;ristiques graphiquesUne propri&#233;t&#233; essentielle des graphes polynomiaux est qu&#8217;ils sont lisses et continus, sans ruptures, trous ni angles vifs. Par exemple, le graphe d&#8217;un polyn&#244;me lin&#233;aire est une droite, celui d&#8217;un polyn&#244;me quadratique est une parabole, et les polyn&#244;mes de degr&#233; sup&#233;rieur peuvent g&#233;n&#233;rer des courbes plus complexes comportant des points d&#8217;inflexion et plusieurs extrema locaux. Les transformations telles que les sym&#233;tries, les translations verticales ou horizontales et les dilatations modifient la position ou l&#8217;&#233;chelle du graphe, sans en changer le degr&#233;.Z&#233;ros et th&#233;or&#232;me des valeurs interm&#233;diairesLes z&#233;ros d&#8217;un polyn&#244;me sont les valeurs de x pour lesquelles P(x) = 0 &#160;; graphiquement, ils correspondent aux points d&#8217;intersection avec l&#8217;axe des abscisses. Le th&#233;or&#232;me des valeurs interm&#233;diaires &#233;nonce que si un polyn&#244;me continu prend des signes oppos&#233;s en deux points distincts, alors il existe au moins un z&#233;ro entre ces deux points. Ce th&#233;or&#232;me joue un r&#244;le essentiel dans la d&#233;termination des z&#233;ros et dans la construction de graphes polynomiaux pr&#233;cis.

Fonctions polynomiales et leurs graphes

Les fonctions polynomiales constituent des &#233;l&#233;ments fondamentaux de l&#8217;alg&#232;bre et de l&#8217;analyse. Elles sont d&#233;finies par des ...

Education

Enseignement

JoVE Core

Math Fundamentals

Fondamentaux des mathématiques

Unit

Unité

Polynomial and Rational Functions

Fonctions polynomiales et rationnelles

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

Introduction to Polynomial Functions

polynomial graphs, zeros, and degree

Polynomial functions are an important part of algebra and calculus. They are made from variables and constants combined by addition, subtraction, and multiplication. The variable is raised to a nonnegative integer exponent. A general polynomial function of degree n has a leading term aₙxⁿ, where aₙ is not equal to 0. The coefficient aₙ is the leading coefficient, and a₀ is the constant term.

Polynomials are grouped by degree. A constant function has degree zero, a linear function has degree one, and a quadratic function has degree two. Higher degrees continue the pattern. The degree affects the maximum number of turning points and helps determine the overall graph shape. Odd-degree polynomials extend in opposite directions as x approaches plus or minus infinity. Even-degree polynomials extend in the same direction.

Polynomial graphs are smooth and continuous. They do not have breaks, holes, or sharp corners. A linear polynomial appears as a straight line, while a quadratic appears as a parabola. Polynomials with higher degree can form more complex curves with inflection points and multiple local extrema. Graph transformations, such as reflections, vertical or horizontal shifts, and stretches, change the position or scale of the graph. They do not change the degree.

Zeros are another key feature of polynomial functions. A zero is a value of x for which P(x) = 0, and it appears on the graph as an x-intercept. The Intermediate Value Theorem helps locate zeros. If a continuous polynomial has opposite signs at two points, then at least one zero must lie between them. This idea is useful for finding zeros and building accurate polynomial graphs.

Polynomial Graphs, Zeros, and Degree

quadratic models

Quadratic Motion and Parabolas

Quadratic models describe relationships where the rate of change changes at a constant rate. In math and science, this often shows up as a curved pattern called a parabola. These models help explain how a system changes over time or under a set force. A common example is the vertical motion of an object moving under gravity, such as a ball thrown into the air. The object rises to a maximum height and then falls back down. Gravity slows the ascent and speeds up the descent, which creates the...

introduction to polynomial functions

Polynomial functions are an important part of algebra and calculus. They are made from variables and constants combined by addition, subtraction, and multiplication. The variable is raised to a nonnegative integer exponent. A general polynomial function of degree n has a leading term aₙxⁿ, where aₙ is not equal to 0. The coefficient aₙ is the leading coefficient, and a₀ is the constant term. Polynomials are grouped by degree. A constant function has degree zero, a linear function has degree...

long division of polynomials

Polynomial Division: Quotient and Remainder

Polynomial division breaks a polynomial into a quotient and a remainder. It works like numerical division, but the dividend is a polynomial and the divisor is an algebraic expression. The result shows how much of the divisor fits into the dividend and what is left over. The first step is to write both polynomials in standard form, with terms in descending powers of the variable. Then divide the leading term of the dividend by the leading term of the divisor. That first result becomes the first...

synthetic disvision of polynomials

Using Synthetic Division to Find Factors

Synthetic division is a fast way to divide a polynomial by a linear binomial of the form x - c, where c is a real number. It gives a shorter method than polynomial long division and is useful for checking values and finding factors. The setup starts with the coefficients of the polynomial written in descending order of powers. If a term is missing, a zero must be used to keep the columns lined up. The constant c from the divisor x - c is placed to the left of the synthetic division table. The...

real zeros of polynomials

Finding Polynomial X-Intercepts

Polynomials can be analyzed by finding their real zeros, which are the values of x that make the polynomial equal to zero. These points are also the x-intercepts of the graph. Understanding them helps students see where a polynomial crosses the x-axis. The Rational Zeros Theorem gives a list of possible rational solutions for a polynomial with integer coefficients. If f(x)=anx^n+...+a0, then every rational zero has the form p/q. In that form, p divides the constant term a0 and q divides the...

fundamental theorem of algebra

Polynomial Roots in Complex Numbers

Polynomial roots in complex numbers are a key result in algebra. The Fundamental Theorem of Algebra says that every non-constant polynomial with complex coefficients has at least one complex zero. For a polynomial of degree n, where n is at least 1 and the leading coefficient a n is not 0, there is at least one solution in the complex number system. This result also applies to polynomials with real coefficients, because the real numbers are a subset of the complex numbers. The Complete...

complex zeros

Finding Polynomial Roots With Complex Numbers

Complex numbers help describe every root of a polynomial equation. A complex number has the form a + bi, where a and b are real numbers and i is the imaginary unit, with i^2 = -1. A complex zero is any value that makes P(x) = 0 for a polynomial P(x). The complex number system includes the real numbers, so it gives a complete way to study polynomial roots. Every polynomial of degree n  1 can be written as a product of n linear factors over the complex numbers. In that factorization, each c_i...

asymptotes in rational functions

Graphing Rational Functions with Asymptotes

Rational functions are quotients of two polynomials, with the denominator Q(x) not equal to zero. Their graphs often include asymptotes, which are lines the graph gets close to but does not touch. These lines help show how the function behaves near certain input values and at large values of x. A vertical asymptote appears when the denominator is zero and the numerator is not zero. At those x-values, the function is undefined. To find a vertical asymptote, solve Q(x) = 0. For example, a...

introduction to nonlinear inequalities

Graphing and Solving Nonlinear Inequalities

Linear and nonlinear inequalities help describe variable relationships and the ranges that satisfy a condition. A linear inequality uses variables raised only to the first power. Its graph is a straight line that divides the coordinate plane into two regions. One region satisfies the inequality, and the other does not. Nonlinear inequalities use variables raised to powers greater than one. These include quadratic inequalities and higher-degree polynomial inequalities. Their graphs are curved,...

application of nonlinear inequalities

Solving Nonlinear Inequalities on a Number Line

Nonlinear inequalities can be solved by checking where an expression is positive or negative on a number line. These inequalities often include squares, products, or variables in the denominator, so they do not follow the same simple pattern as linear inequalities. The first step is to rewrite the inequality so that zero is on one side. After rewriting, factor the expression if possible. Factoring helps you find the key values where the expression equals zero. In one example, the values 3 and...

key terms and concepts

Explore polynomial degree, graph shape, zeros, and the Intermediate Value Theorem. Learn how polynomial functions stay smooth, continuous, and graphable.

Polynomial Graphs, Zeros, and Degree | JoVE K12

The JoVE Math Fundamentals collection is designed to build a deep and comprehensive understanding of essential mathematics. Covering the foundations of algebra, geometry, trigonometry, and analytic reasoning, this course establishes a strong base for future studies. The collection connects core mathematical concepts with real-world practice, equipping learners to solve complex problems, master problem-solving skills, and apply abstract ideas.

math fundamentals

Polynomial Graphs, Zeros, and Degree

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