key term - Roots

Definition

In mathematics, the term 'roots' refers to the values of a variable for which a given equation or function equals zero. Roots are fundamental concepts that are deeply intertwined with various topics in pre-calculus, including quadratic functions, polynomial functions, and radical functions.

5 Must Know Facts For Your Next Test

1. The roots of a quadratic function are the $x$-intercepts of the parabola, which can be found using the quadratic formula or by factoring the function.
2. The degree of a polynomial function is determined by the highest exponent of the variable, and the number of roots of the function is equal to the degree of the function.
3. Graphing polynomial functions can help visualize the roots of the function, which are the $x$-intercepts of the graph.
4. Dividing polynomials can be used to find the roots of a polynomial function, as the roots are the values of $x$ for which the quotient is zero.
5. The inverse of a radical function is a power function, and the roots of the radical function are the $x$-intercepts of the power function.

Review Questions

• Explain how the roots of a quadratic function relate to the graph of the function.
  • The roots of a quadratic function are the $x$-intercepts of the parabolic graph of the function. These roots can be found using the quadratic formula or by factoring the function. The location of the roots on the graph determines the shape and orientation of the parabola, as well as the behavior of the function, such as the minimum or maximum point and the range of the function.
• Describe the relationship between the degree of a polynomial function and the number of roots it can have.
  • The degree of a polynomial function is determined by the highest exponent of the variable in the function. The number of roots of a polynomial function is equal to the degree of the function, with the exception of complex roots. For example, a quadratic function (degree 2) can have up to two real roots, a cubic function (degree 3) can have up to three real roots, and so on. This relationship is crucial in understanding the behavior and properties of polynomial functions.
• Explain how dividing polynomials can be used to find the roots of a polynomial function.
  • Dividing one polynomial by another can be used to find the roots of the polynomial function. The roots of the polynomial function are the values of $x$ for which the quotient is zero. This process is known as polynomial division, and it can be used to factor the polynomial and identify its roots. By finding the factors of the polynomial, you can determine the values of $x$ that make the function equal to zero, which are the roots of the polynomial function.

Related terms

Quadratic Equation:

A polynomial equation of the form $ax^2 + bx + c = 0$, where $a$, $b$, and $c$ are real numbers, and $a \neq 0$. The solutions to a quadratic equation are called the roots of the equation.

Polynomial Function:

A function that can be expressed in the form $f(x) = a_nx^n + a_{n-1}x^{n-1} + \dots + a_1x + a_0$, where $a_n, a_{n-1}, \dots, a_1, a_0$ are real numbers and $n$ is a non-negative integer. The roots of a polynomial function are the values of $x$ for which the function equals zero.

Radical Function:

A function that involves a root, such as a square root or a cube root, as a part of the function. The roots of a radical function are the values of $x$ for which the function equals zero.