+0  
 
0
1320
3
avatar+647 

What is the range of the function (3x+1)/(x+8)

 Oct 22, 2017
 #1
avatar+129852 
+2

It will have a horizontal asymptote  at   y = 3

 

The range will be  ( - infinity, 3) U ( 3 , infinity )

 

 

cool cool cool

 Oct 22, 2017
 #2
avatar+118677 
+3

What is the range of the function (3x+1)/(x+8)

 

I am not sure how CPhill looked at this question. This is what I'd do.

Chris may well have an easier way to look at it  laugh

x cannot equal -8 because the denominator cannot be equal to zero.

If I do the algebraic division here then   

\(f(x)=\frac{3x+1}{x+8}=3+\frac{-23}{x+8}\\ Now\;\;\frac{-23}{x+8}\;\;\text{cannot equal 0 so } f(x)\ne 3\\ Also\\ y=\frac{-23}{x+8}+3\\ \text{is of the from }y=\frac{a}{x-h}+k \\ \text{so it must be a hyperbola with asymptotes at x=-8 and y=3.}\)

 

the range Chris gave is certainly correct, I just wanted to discuss the question more. :)

 

 Oct 22, 2017
edited by Melody  Oct 22, 2017
 #3
avatar+129852 
+2

I should have expanded my answer a tad bit more

 

We will have a vertical asymptote  ar x  =  -8

 

As the graph approaches x = -8 from the left , the graph will approach infinity

 

As the graph approaches x = -8 from the right , the graph will approach  -infinity

 

And there is a horizontal asymptote at y = 3  which is not crossed by the graph

 

So.....the range is   ( - infinity, 3) U ( 3 , infinity )

 

 

cool cool cool

 Oct 22, 2017

4 Online Users

avatar