Quadratic functions

Whether your application is business, how-to, education, medicine, school, church, sales, marketing, online training or just for fun, PowerShow. And, best of all, most of its cool features are free and easy to use.

Quadratic functions

We know that linear equations graph a straight line, so I wonder what a quadratic function is going to look like?


Let's take a look! A quadratic function is always written as: The graph of a quadratic function is called a parabola. A parabola contains a point called a vertex.

The parabola can open up or down. If the parabola opens up, the vertex is the lowest point.


This point is called the minimum point. If the parabola opens down, the vertex is the highest Quadratic functions. This point is called the maximum point A parabola also contains two points called the zeros or some people call these the x-intercepts.

The zeros are the points were the parabola crosses the x-axis. Now, we will use a table of values to graph a quadratic function. Remember that you can use a table of values to graph any equation.

There are a few tricks when graphing quadratic functions. We must make sure that we find a point for the vertex and a few points on each side of the vertex.

Graphing Quadratic Functions

Using a Table of Values to Graph Quadratic Functions Notice that after graphing the function, you can identify the vertex as 3,-4 and the zeros as 1,0 and 5,0. So, it's pretty easy to graph a quadratic function using a table of values, right?

It's just a matter of substituting values for x into the equation in order to create ordered pairs. There are a lot of other cool things about quadratic functions and graphs. Locate the vertex on the completed table of values. Do you notice any patterns? Look specifically at the f x values.

Notice how the f x values start to repeat after the vertex? Quadratic functions are symmetrical. If you draw an imaginary line through the vertex, this is called the axis of symmetry. Now check out the points on each side of the axis of symmetry. Use the table of values to graph the following function: Answer Key Notice that the zeros of the function are not identifiable on the graph.

They contain decimals which we can not accurately read on this graph. The vertex for the parabola is -3,8. This parabola opens down; therefore the vertex is called the maximum point. Can you guess which factor in the function determines whether the parabola opens up or down?

It's the sign of the first term the squared term. If a is negative, the parabola opens down and the vertex is the maximum point.

Quadratic functions

For more help with quadratic functions, see lesson 2 on quadratics. Need Help With Your Homework? Try this calculator for step by step answers with subscription.Quadratic Equations Explained A quadratic equation is an equation that looks like this: ax 2 +bx+c = 0, where a, b, and c are numbers, called coefficients.

Example: x 2 +3x+4 = 0. You can think about a quadratic equation in terms of a graph of a quadratic function, which is called a parabola.

The equation means that you have to find the points. Quadratic Functions. A quadratic function has the form f(x) = ax 2 + bx + c, where a, b, and c are real number constants and a ¹ 0. Its domain is all real numbers. The constants a, b, and c are called the coefficients of the quadratic function.

Modeling with Quadratic Functions Writing a Quadratic in Standard Form In this activity you will write a quadratic function in standard form, y = ax2 + bx + c, for the parabola in Example 2.

The parabola passes through (º2, 0), (º1, 2), and (3, 0).


Substitute the. Quadratic equations lend themselves to modeling situations that happen in real life, such as the rise and fall of profits from selling goods, the decrease and increase in the amount of time it takes to run a mile based on your age, and so on. DrDelMath Important Properties of Quadratic Functions.

Copyright by All Rights Reserved. Use of text, images and other content on this website are subject to. A Quadratic is a polynomial function where quadratic stands for the fatc that 2 is the highest exponent of X. The two zeros in this equation and graph are (,0) and (,0), but the only zero that matters in this word problem is the positive zero for a ball can be thrown.

Quadratic Function Homework Help