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

一个被踢出的足球沿曲线路径运动，该路径可用二次多项式建模。多项式函数使用加法、减法或乘法将常数和变量组合在一起，其中变量被提升为非负整数次幂。最高次幂的项称为首项，其系数称为首项系数。多项式根据其次数进行分类，其次数是指变量具有最高幂次的项。多项式函数的图像平滑且连续。一次多项式的图像是一条直线，二次多项式的图像呈U形曲线，而更高次的多项式则产生更加弯曲的图像，并可能具有更多的拐点。奇数次多项式的图像向相反方向延伸，而偶数次多项式的图像向相同方向延伸。多项式的零点是指函数值等于零的&#8239;x&#8239;值，此时图像与x轴相交或相切。线性函数是多项式的一个典型例子，它满足介值定理。该定理指出，如果一个函数是连续的，并且在某一点的输出值为正，在另一点的输出值为负，那么它的图像在这两点之间必然穿过x轴。

多项式函数及其图像

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Education

教育

JoVE Core

Math Fundamentals

数学基础

Unit

单位

Polynomial and Rational Functions

多项式与有理函数

KEY TERMS AND CONCEPTS

关键术语与概念

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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