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Topic: positive exponents
Replies: 7   Last Post: May 13, 1995 1:20 PM

 Messages: [ Previous | Next ]
 Richard Stephen Lewis Posts: 1 Registered: 12/6/04
Re: positive exponents
Posted: May 10, 1995 10:37 AM

The most probable reason we eliminate negative exponents is for the same
reason we rationalize radicals in the denominator...to make the value
easier to compute in the days before calculators. For example 1/sqr(2)
would be computed by dividing 1 by 1.414 whereas if I rationalize first,
I would only have to divide 1.414 by 2. Likewise 2 raised to the -4
power could be computed by dividing 1 by 16. Now that we are in the age
of calculators and computers, some of our old rules have become not as
important.

Richard Lewis
Dulles High School
Ft. Bend I.S.D.
Sugar Land, Texas

On Wed, 10 May 1995, KIMBERLY FATH wrote:

> Hi! I'm new to the list for the second time and alreasy have a question for
> you knowledgeable folks.
>
> I am teaching an introductory algebra class at my institution. Yesterday,
> one of my students asked me why we eliminate negative exponents. I gave him
> my pitiful explanation (convention, looks neater, makes substituting numerical
> values easier, etc.) but said I would look into who came up with this great
> idea. I've looked in my books and can't find anything- I'm looking for
> something that says "so and so group of people thought this was a good idea"
>
> Any information that any one person can share with me would be appreciated.
> Obviously, e-mail me and I will post a summary.
>
> Thanks,
>
> Kim Fath Saint Xavier University
> fath@sxu.edu Student Success Program
> Learning Assistance Services
>