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noideaz_333
Feb 16, 2008, 06:09 PM
I'm new to this but I would appreciate any help on this question:

Let f: D -> R, f(x)=x/(x+1) where D is the largest subset of R for which (f) is defined.

a) Express f(x) in the form f(x) = A/(x+b) + B
I cant's find the B in this equation

b) State D... D is supposedly a restriction

THanks, I really want to learn this one

galactus
Feb 16, 2008, 06:15 PM
For part a, long divide.




------------------------
x+1|x



For part b, what may be meant by D is the domain of said function.

The domain will be all values except where you have division by 0.

What value of x results in division by 0?

noideaz_333
Feb 16, 2008, 06:21 PM
SOrry I didn't understand that

galactus
Feb 16, 2008, 06:34 PM
SOrry I didn't understand that

Didn't understand what? How to long divide? It's clear that in the denominator you have x+1. What value of x makes this equal 0? Therefore, you have division by 0 at that point and it is undefined and not in the domain.

noideaz_333
Feb 16, 2008, 06:40 PM
Are you referring to part a long dividing??

galactus
Feb 17, 2008, 05:28 AM
I am referring to both. Part a, can you long divide an algebraic expression?

For part b, it's rather straight forward. Think domain. Do you know what a domain is?

All values except for -1 are in the domain. -1 results in division by 0... a big no-no in the math world.