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mathmarauder

Junior Member
Joined
Oct 25, 2008
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f(x) = x+1/(x-2)(x+2)

For this problem do i start by using the normal?
x-2 = 0
x = 2
x + 2 = 0
x = -2
then from here my first two points on the graph are
(2,0),(-2,0) if this is correct...where do i go from here?
also how does x+1/ play a part in this?
 
mathmarauder said:
f(x) = x+1/(x-2)(x+2)

For this problem do i start by using the normal?
x-2 = 0
x = 2
x + 2 = 0
x = -2
then from here my first two points on the graph are
(2,0),(-2,0) if this is correct...where do i go from here?
also how does x+1/ play a part in this?
Click to expand...
Is your problem

\(\displaystyle f(x) \, = \, x \, + \, \frac{1}{x-2}\cdot (x+2)\)

or

\(\displaystyle f(x) \, = \, \frac{x+1}{x-2}\cdot (x+2)\)

or

\(\displaystyle f(x) \, = \, \frac{x+1}{(x-2)\cdot (x+2)}\)

or something else....

Hint:

Find at which value of x you have f(x) = 0

Find at which value of x you have f(x) = undefined (when is a function undefined?)
 
mathmarauder said:
original problem was
x+1/x^2-4
Click to expand...

Since you did not use any parenthesis - your problem now reads:

\(\displaystyle f(x) \, = \, x \, + \, \frac{1}{x^2} \, - \, 4\)

This is totally different from what you had presented before.

However, same hints apply -
Find at which value of x you have f(x) = 0

Find at which value of x you have f(x) = undefined (when is a function undefined?)
Click to expand...

and show us what you get utilizing those hints.
 
mathmarauder said:
f(x) = (x+1)/(X^2-4) Is the problem...
using the hints.
x = -1 <<< What happens here
x = -2 <<< What happens here

Also consider what happens at x = -2

What is the significance of function being undefined? What happens there?
?
Click to expand...
 
x= -1 turns into (-1,0)
x = -2 turns into (-2,0)
Thw significance of it being undefined...
i dont know.
 
mathmarauder said:
x= -1 turns into (-1,0)
x = -2 turns into (-2,0)
Thw significance of it being undefined...
i dont know.
Click to expand...

What references have you used to find out - The significance of it being undefined ?

go to

google.com

type in

function undefined

you'll find 4.3 million sites ready to help you with interactive examples.

More specifically go to:

http://mathforum.org/library/drmath/view/64263.html
 
I know that undefined meant not defined :)
I just thought if for example x = -1 or (-1,0) that it was defined.
 
mathmarauder said:
I know that undefined meant not defined :)

Yes - but it has special significance in regard to the graph. You need to find out what that is - how does the function behave (graphically) around that point.

I just thought if for example x = -1 or (-1,0) that it was defined.
Click to expand...
 
Ok so my guess is...
what you are saying is that...the opposite points
are used as well.
so like (-2,0) and (0,-2)?
Has anything I've done been correct?
 
Yes I read it.
I appreciate your effort,
but I am not closer to solving this problem.
I am certain it is due to my ignorance in this field,
so once again thank you for your effort.
 
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