🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

2 total messages Started by Mike Bolduan Thu, 21 Jan 1993 17:41
Re: INTEGRALS
#497
Author: Mike Bolduan
Date: Thu, 21 Jan 1993 17:41
41 lines
1866 bytes
David Radcliffe:

YES!!!!
You said it much better than I could have. It is a matter of 
definition and a definition is "what we say it is". We have the 
right to define anything we want in any way we wish. It is a 
"bad" definition (and hence should probably not have been 
made) if it leads to "nastiness" (e.g., contradictions) down the 
road.
This reminds me just a tad about the huge debate a couple of 
years ago about the meaning of 0^0. (and please let's just let 
sleeping dogs lie!)This also is a matter of how we wish to 
define something.
If I had read a bit more about improper integrals I would 
have quickly found the part that defines the "sum" of two 
integrals as divergent if EITHER (or both) of the integrals 
which make it up are divergent. This is the case here, so: end 
of story. The integral of 1/x from -1 to 1 is divergent and 
NOT ZERO. Sometimes "common sense" takes it in the ear...   
:-)
BTW I would highly recommend a couple of books for 
people interested in calculus as it (should) be taught these 
days:
1) The new material by the Harvard Consortium published 
by Wiley
2) The book by Dick and Patton which integrates (sorry 
'bout that!   :-))  technology into the class)
3) Calculus by Gilbert Strang which is a VERY interesting 
book (although 'tain't cheap!)

Looks like I got folks thinking a bit. Neat-O
mike



bolduan@catseq.catlin.edu    internet
bolduan@catlin     bitnet
-- 
mike bolduan
bolduan@catlin
Re: INTEGRALS
#512
Author: I am a terminator.
Date: Mon, 25 Jan 1993 16:55
52 lines
2661 bytes
In article <1jmn8cINN3n9@usenet.INS.CWRU.Edu>, cb919@cleveland.Freenet.Edu (Mike Bolduan) writes:
|> 
|> David Radcliffe:
|> 
|> YES!!!!
|> You said it much better than I could have. It is a matter of 
|> definition and a definition is "what we say it is". We have the 
|> right to define anything we want in any way we wish. It is a 
|> "bad" definition (and hence should probably not have been 
|> made) if it leads to "nastiness" (e.g., contradictions) down the 
|> road.

The definition may not be so bad. It get's us away from a lot of
trouble (see <1jkfe8INN7ou@access.usask.ca>). How can you >> verify <<
the limit to be zero when it heads to -infinity coming from the left
and to +infinity coming from the right?

|> This reminds me just a tad about the huge debate a couple of 
|> years ago about the meaning of 0^0. (and please let's just let 
|> sleeping dogs lie!)This also is a matter of how we wish to 
|> define something.

Hmm. What can you do? Consider lim x->0 0^x. Then consider
lim x->0 x^0. Then consider the definition of exponentiation.
a^x means exp(x ln a). But ln x is not defined at x=0 !

|> BTW I would highly recommend a couple of books for 
|> people interested in calculus as it (should) be taught these 
|> days:
|> 1) The new material by the Harvard Consortium published 
|> by Wiley
|> 2) The book by Dick and Patton which integrates (sorry 
|> 'bout that!   :-))  technology into the class)
|> 3) Calculus by Gilbert Strang which is a VERY interesting 
|> book (although 'tain't cheap!)

I really like Modern Calculus and Analytic Geometry by R.A. Silverman.
I got it used for $8. It looked like new though, so I pity the previous
owner.

-- 

Henry Choy
choy@cs.usask.ca

What rolls down stairs alone or in pairs            This has been brought to 
Rolls over your neighbor's dog?                     you by the numbers 4
What's great for a snack and fits on your back?     and 9 and the letter P.
It's Log, Log, Log!  -- "The Log Song", from            -- Big Bird
                         Ren & Stimpy

Math is tough!       -- Barbie
Thread Navigation

This is a paginated view of messages in the thread with full content displayed inline.

Messages are displayed in chronological order, with the original post highlighted in green.

Use pagination controls to navigate through all messages in large threads.

Back to All Threads