How do you graph y=3x3, compare to the parent graph, and state the domain and range?

1 Answer
Feb 4, 2018

Graph it using a graphing calculator, domain is {xx0,xR}, range is {yy3,yR}

Explanation:

If you do not have a graphing calculator, you can use one that is online and free, such as Desmos. Here is the link: Desmos

There are buttons at the bottom of the screen that can be used to enter your function. The parent function is x. You can also graph that function to see how it compares to your transformed function.

The way to write your function in standard form is as following:
ab(x+c)+d, where b and c are horizontal transformations and a and d are vertical. This link provides a more detailed explanation: Transformations

The first and most obvious thing about this transformation was that it was reflected over the x-axis. That can be seen in your function because the leading coefficient (a) is negative. Next, your graph has been translated down three units. This is shown in your equation because d is negative 3. Lastly, your graph has been vertically stretched by a factor of 3, since |a|=3

Finally, the domain and range. This can be figured out graphically, by looking at the graph and seeing that x must be greater than 0 and y must be less than -3. So, {xx0,xR}, and {yy3,yR}.