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Topic: Help with limit problem?
Replies: 12   Last Post: Sep 15, 2007 11:09 PM

 Messages: [ Previous | Next ]
 Brian M. Scott Posts: 1,289 Registered: 12/6/04
Re: Help with limit problem?
Posted: Sep 11, 2007 1:34 PM

On Tue, 11 Sep 2007 12:12:49 -0500, <me@privacy.net> wrote
in <news:u2jde3p58p2g8b6lchak0ipm3mtf2rsunf@4ax.com> in

> ooo <x@x.invalid> wrote:

>>If this is the limit,

>> lim[x -> 0] (x^4 - 1) / (x^3 - 1)

>>why do you want to factor it?

> Its the function of x

> Need limit value as it approaches zero

What ooo is getting at is that in this problem there's no
need to factor the numerator or the denominator: the limit
as x approaches 0 can be obtained directly from the fraction
(x^4 - 1)/(x^3 - 1) without any manipulation.

If you were taking the limit as x approaches 1, it would be
another story: then the numerator and denominator would both
be approaching 0, and you *would* have to find a common
factor of x^4 - 1 and x^3 - 1 to cancel. (As Arturo has
already pointed out, x - 1 is such a factor.)

> VERY new to all the lingo so bear with me. <G>

Brian

Date Subject Author
9/11/07 lloyd
9/11/07 magidin@math.berkeley.edu
9/11/07 Driveby
9/11/07 lloyd
9/11/07 Brian M. Scott
9/11/07 lloyd
9/11/07 lloyd
9/11/07 magidin@math.berkeley.edu
9/11/07 Driveby
9/14/07 lloyd
9/15/07 Darrell
9/15/07 Darrell
9/12/07 Hanford Carr