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Re: [apcalculus] rationalizing the denominator
Posted:
Aug 28, 2012 12:20 PM


In Calculus it is sometimes necessary to move a radical INTO the denominator in order to determine a limit, so rationalizing all denominators is pointless, IMO. In Precalculus, we begin explaining this to students, and in AP Calculus, we point out that it is not necessary. On the AP exam, any mathematically correct form of the answer is accepted, so I actually encourage them to leave their answers in the form that they get, radical in the bottom or not. Since some textbooks persist in rationalizing the denominators, I just tell the students to check to see if the solutions are equivalent by evaluating both on the calculator (just for checking, not answering the question using a calculator).
HTH, Carole
On Tue, Aug 28, 2012 at 7:19 AM, allison heyl <alheyl@yahoo.com> wrote:
> > How do people feel about rationalizing the denominator? (especially unit > circle). Some books are now leaving the radical in the denominator and I > am not sure what to tell my students. > > Thanks > Allison > > > ==== > Course related websites: http://apcentral.collegeboard.com/calculusabhttp://apcentral.collegeboard.com/calculusbc > > To search the list archives for previous posts go to > http://lyris.collegeboard.com/read/?forum=apcalculus > > To unsubscribe use this URL: http://lyris.collegeboard.com/read/my_forums/ > > To change your subscription address or other settings use this URL: > http://lyris.collegeboard.com/read/my_account/edit >

*Carole Stevens *Monsignor Kelly Catholic High School<http://www.monsignorkellyhighschool.com/> 4098662351 ext 159 4098600874 fax CStevens@MKCHS.com
==== Course related websites: http://apcentral.collegeboard.com/calculusab http://apcentral.collegeboard.com/calculusbc  To search the list archives for previous posts go to http://lyris.collegeboard.com/read/?forum=apcalculus To unsubscribe click here: http://lyris.collegeboard.com/read/my_forums/ To change your subscription address or other settings click here: http://lyris.collegeboard.com/read/my_account/edit



