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Topic: [math-learn] Transforming formulas
Replies: 55   Last Post: Feb 19, 2007 11:48 PM

 Messages: [ Previous | Next ]
 Paul A. Tanner III Posts: 5,920 Registered: 12/6/04
Re: [math-learn] Re: Transforming formulas
Posted: Feb 4, 2007 1:09 AM
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--- elkashish <forums@learningbyyourself.com> wrote:

>
> I very much agree that the tension between language, thought, and
> mathematics is a key issue [see my word problems book excerpt to what
> I view as a way to overcome it].
>
> I would (counterfactually? ;-)] be careful about using
> counterfactuals
> with students. The reason is exactly because of the problem I believe
> many have with it (illustrated in the example below). The reason is
> that counterfactuals require more mental processes than factual
> language. One has to hold both states in his mind when one is using
> counterfactuals. It's more accurate mathematically (logic wise) but
> more complex thinking wise.
>
> Thus, I prefer them to simplify the language and then translate to
> mathematics.
>

But is it? All I'm saying is that after seeing students (including when
I was a student) struggle and struggle with trying to make sense of the
conditional, and teachers trying and trying to explain it, I kept
asking myself, "Why doesn't the teacher just change the tense of the
verb?" Is is really less simple language to use a tense other than the
present tense? We have children pretend things all the time, using the
counterfactual tense. Example: As a creative writing exercise, we could
have them fill in the blank in "If I were a bird, then _____." I don't
see that it's necessarily more simple and more appropriate language to
use the present tense, and ask, "If I am a bird, then _____."

Another example, in the math realm: Which question would more likely
cause less of a problem for students, the first one using the
counterfactual tense, or the second one using the present tense? (1) If
Earth's radius were the same as Jupiter's, then what would be Earth's
circumference? (1) If Earth's radius is the same as Jupiter's, then
what is Earth's circumference?

Paul

Date Subject Author
1/28/07 Antonija Horvatek
1/28/07 John Morse
1/28/07 Zeev Wurman
1/28/07 Ed Wall
1/28/07 Richard Sisley
1/29/07 Rex Boggs
1/29/07 Rex Boggs
1/29/07 John Morse
1/29/07 Chris
1/29/07 John Morse
1/29/07 Antonija Horvatek
1/29/07 John Clement
1/30/07 Paul A. Tanner III
1/30/07 Joshua Zucker
1/31/07 Paul A. Tanner III
1/31/07 Moti
1/31/07 Paul A. Tanner III
1/31/07 timotha@comcast.net
2/1/07 Moti
2/1/07 Antonija Horvatek
2/1/07 John Clement
2/2/07 timotha@comcast.net
2/2/07 John Clement
2/2/07 timotha@comcast.net
2/2/07 Moti
2/2/07 Paul A. Tanner III
2/3/07 Moti
2/3/07 John Clement
2/5/07 Moti
2/5/07 Ed Wall
2/8/07 John Morse
2/4/07 Paul A. Tanner III
2/5/07 Moti Levi
2/4/07 Antonija Horvatek
2/2/07 Ralph A. Raimi
2/3/07 Moti
2/3/07 Ralph A. Raimi
2/4/07 Moti
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2/5/07 Alva
2/5/07 Moti Levi
2/5/07 John Clement
2/5/07 Ed Wall
2/5/07 John Clement
2/5/07 Ed Wall
2/5/07 Moti
1/30/07 John Clement
1/31/07 Antonija Horvatek
1/31/07 Paul A. Tanner III
2/1/07 Moti
2/1/07 Antonija Horvatek
2/1/07 Antonija Horvatek
1/29/07 Paul A. Tanner III
1/30/07 Jerome Epstein
2/19/07 Jon Wilson
1/30/07 Jerome Epstein