Thread: Rational function graphing

This is a general question. How do you figure out how many curves there are in a rational function graph. I know that there are curves at the zeroes, but I saw that there were curves that do not cross any zeroes. How do you find these?

Hi hellojellojw

The curve depends on the equation of the function. I think you can start by using google to learn about it.

Uhh...I mean I know how to graph rational functions. I find the zeroes, horizontal, diagonal, and or vertical asymptotes, and then graph. Now when I graph, I use a sign line and figure out all the curves that cross the zeroes. What I do not get, is why there are more curves than zeroes. I did some research, and I think the answer is just to plug in numbers on either side of the vertical asymptotes to find coordinates?

Hi hellojellojw

I don't get what you mean by "there are more curves than zeroes". Maybe you can explain more or give an example of the graph?

I think he might be talking about when he makes a table and starts plugging in numbers to make the actual curves. There could be some horizontal and vertical asymptotes but the number of curves is the number of zeros that make up those asymptotes.

I think at least.

You can never cross a vertical asymptote, but you can find that you can cross a y-asymptote.