Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.



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 alt.math.undergrad:
> 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



