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

 Messages: [ Previous | Next ]
 magidin@math.berkeley.edu Posts: 11,749 Registered: 12/4/04
Re: Help with limit problem?
Posted: Sep 11, 2007 11:52 AM

In article <s7ede3d44iftv6e0r72q0s6km4ihoc3d48@4ax.com>,
<me@privacy.net> wrote:
>Taking Calc 1
>
>One problem I'm working on is to find Limit as x
>approaches zero for x raised to 4 power minus one over
>x raised to three power minus one
>
>I'm stuck trying to factor it1
>

Synthetic or long division. If a polynomial p(x) evaluates to 0 when
you plug in a number a, then x-a divides p(x).

In this case, both x^4 - 1 and x^3 - 1 evaluate to 0 when you plug in
1, so you can factor x-1 from both. Do long division to see what you
get, cancel the factor of x-1 from the quotient, lather, rinse, and
repeat.

--
======================================================================
"It's not denial. I'm just very selective about
what I accept as reality."
--- Calvin ("Calvin and Hobbes" by Bill Watterson)
======================================================================

Arturo Magidin
magidin-at-member-ams-org

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