Domain and Range

Chapter 4, Section 1: Domain and Range
In this lesson, we learned how to find the domain and range of graphs, the zeroes, and how to determine if its a function or not.
To find the..
-domain: the interval of x values where the graph exists
-range: the interval of y values where the graph exists
-zeroes: x intercept, root- set equal to 0, solve for x
-For the graph to be a function, it must pass the vertical line test.
*If you're given points, the domain will be the list of all x values, and the range will be the list of all y values in { }.

Here's how to find the domain and range of polynomials(very simple!):
The domain is always: (-infinity, infinity). The range is always (-infinity, infinity).

Example 1: Find the domain and range of the following: f(x) = 4x^3 + 2x^2 + 6x - 12
-Domain: (-Infinity, infinity)
-Range: (-infinity, infinity)

Example 2: Find the domain and range of the following: f(x) = -3x^2 +4x - 6
-Domain: (-infinity, infinity)
-Range: (-infinity, -4/2(-3)) = (-infinity, 2/3)