Finding Asymptotes

[DBsWifeLB]

Excel Algebra graphing.
Can someone help me to figure out how to enter f(x)=(2+x)/(1-x)
I am having a heck of a time trying to get this graphed. I also nee
to find the vertical and horizontal asymptotes.
Thanks in advance!
L

 

[Earl Kiosterud]

LB,

You need to provide a bunch of x values in a column, and in an adjacent
column, your f(x). If the x values are in A2 and down, the first formula
would be

=(2+A2)/(1-A2)

Copy it down with the fill handle (lower right corner of cell. Now select
both columns, and make a scatter chart.

At x=1 you'll get an error (that'll drive the chart nuts). Guess that's one
way to find the asymptotes!

 

[BenjieLop]

FYI, I also tried Excel graphing the equation and it looks like th
graph went haywire.

I do not know if this will help you but I did this the old fashione
way (manually) and the graph looks like this (I hope I can explain i
very clearly).

There are two graphs. Properties of the first graph are as follows:

1. It starts from the 3rd quadrant;
1. It crosses the x-axis at x = -2;
2. It crosses the y-axis at y = 2;
3. The vertical asymptote is at x = 1.

Properties of the second graph are as follows:

1. It is located in the 4th quadrant;
2. The vertical asymptote is still at x = 1;
3. It also becomes asymptotic with the x-axis

 

[Earl Kiosterud]

Benjie,

The graph will go nuts if one of your x values takes it near the vertical
asymptote. It causes the y axis to scale to a very large value, and all the
other points will be pretty much on the x axis. If you delete those cells,
it might do better. I made one with x values of -2 to 4 in 0.1 increments,
and it worked pretty well,