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Re: [apcalculus] limit from Stu Schwartz
Posted:
Oct 23, 2012 12:31 PM


NOTE: This apcalculus EDG will be closing in the next few weeks. Please sign up for the new AP Calculus Teacher Community Forum at https://apcommunity.collegeboard.org/gettingstarted and post messages there.  Another way to view it might be what we often do for rational functions.
lim_(x  > inf) (3x^4  3x^3 + 5x^2 + 8x  3) = lim_(x  > inf) (3x^4  3x^3 + 5x^2 + 8x  3)/1 = lim_(x  > inf) (3x^4  3x^3 + 5x^2 + 8x  3)/1 * (1/x^4)/(1/x^4) = lim_(x  > inf) [3  3/x + 5/x^2 + 8/x^3  3/x^4]/[1/x^4] > (3 + 0 + 0 + 0 + 0)/(+0) > +/+ inf = + inf
On Mon, Oct 22, 2012 at 9:16 AM, Tammy Slack <tslack@bgcsd.org> wrote:
> NOTE: > This apcalculus EDG will be closing in the next few weeks. Please sign up > for the new AP Calculus > Teacher Community Forum at > https://apcommunity.collegeboard.org/gettingstarted > and post messages there. > >  > Can anyone tell me how to solve the limit as x approaches negative > infinity of (3x^4  3x^3 + 5x^2 + 8x  3)? I assume it is positive or > negative infinity but don't know how to tell which it is. >  > To search the list archives for previous posts go to > http://lyris.collegeboard.com/read/?forum=apcalculus >
 Brian Swanagan, PhD Model High School Mathematics Teacher
 To search the list archives for previous posts go to http://lyris.collegeboard.com/read/?forum=apcalculus



