Finding the Zeros of a Rational Function

In summary, the conversation discusses the process of graphing a rational function and finding its asymptotes and roots. The speaker shares their method of finding the x value for the y-intercept and expresses uncertainty about its accuracy. They also ask for help in understanding how to properly graph asymptotes and find the roots of the function.
  • #1
ghostbuster25
102
0
I have been asked to draw the graph of the function f(x)= (x+3)/(x-2)

I have found where it cuts the y-axis by putting x=0 but am unsure of how to find the x value.
I found the inverse of f(x)= (x+3)/(x-2) which gave me x= (y+3)/(y-2) then set y=0 which again gave me x=-3

I have checked on graphing calculators and this is the correct answer but i think my method is wrong!

Could anyone please help?
 
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  • #2
Information you need to know when you're graphing rational functions include... asymptotes and roots.

Do you know where your horizontal asymptotes are? What about the vertical asymptotes? Beware, because your graphing calculator may or may not show asymptotes properly!

What about the roots of this function?
 
  • #3
(Assuming that the denominator is not zero,) a fraction equals zero if the numerator equals zero. So to find the zeros of the function
[tex]f(x) = \frac{x + 3}{x - 2}[/tex]
set the numerator equal to zero.
 

What is a graph of a function?

A graph of a function is a visual representation of the relationship between inputs and outputs of a mathematical function. It consists of a set of points plotted on a coordinate plane, with the horizontal axis representing the input values and the vertical axis representing the corresponding output values.

How do I draw a graph of a function?

To draw a graph of a function, you will need to plot a series of points on a coordinate plane using the given input and output values from the function. You can then connect these points with a smooth line to get a visual representation of the function.

What is the purpose of drawing a graph of a function?

The main purpose of drawing a graph of a function is to visually represent the relationship between the input and output values of the function. It can also help in understanding the behavior of the function, identifying key features such as zeros, maximum and minimum points, and determining the domain and range of the function.

What are the key elements of a graph of a function?

The key elements of a graph of a function include the x and y-axes, which represent the input and output values respectively, the plotted points, and the line connecting these points. Other important elements may include labels, scales, and a legend to indicate the function being graphed.

What are some common types of functions that can be graphed?

Some common types of functions that can be graphed include linear, quadratic, exponential, logarithmic, and trigonometric functions. Other types of functions, such as rational or polynomial functions, can also be graphed using similar methods.

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