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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

well yeah,but the problems in high school are almost always solvable,at least for regular program of teaching.

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

That is true and it is very dangerous.

**In mathematics, you don't understand things. You just get used to them.I have the result, but I do not yet know how to get it.All physicists, and a good many quite respectable mathematicians are contemptuous about proof.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

i think i know why you think so.for the same reason you fear simplification.

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

Worse than that. It subtly puts into the students mind that all problems have solutions by the standard methods.

**In mathematics, you don't understand things. You just get used to them.I have the result, but I do not yet know how to get it.All physicists, and a good many quite respectable mathematicians are contemptuous about proof.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

thought so.i know you fear general thought.

i think we are going a little bit off-topicy-ish here.so what do you say about the three piece piece-wise functions?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

What exactly are you trying to do with it?

**In mathematics, you don't understand things. You just get used to them.I have the result, but I do not yet know how to get it.All physicists, and a good many quite respectable mathematicians are contemptuous about proof.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

did you even read my question back then?

if i wanted to represent the next function with only one formula,how could i do that? :

*Last edited by anonimnystefy (2012-02-20 06:53:14)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

Yes, I read it but I do not understand it. The purpose of the piecewise notation is to represent functions that can not be represented by one equation, so why are you going backwards?

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

well it may not always be true.

e.g. look at my first post.i showed that the piecewise function:

can be represented with a single formula,so i'm guessing other ones can too.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

Hi anonimnystefy;

That is what I am not quite getting. I need some explanation on what you did there.

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

i started by looking at the graph of y=sgn(x) for all x<>0 where sgn(x) represents the sign function valued +1 for positive values of x and -1 for negative values of x.

then i saw that if we scale and/or translate that graph we get similar graphs where the only thing that changes are the starting points of the two rays.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

That is what I do not understand. You used parameters a and b?

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

if you are wondering what a and b represent in the first place,then i will explain myself.a and b represent the y coordinates of the starting points of those two rays.in my example a=3 and b=1.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

Okay, look at post #32. The piecewise is not defined for lots of points.

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

it's not defined only -1 and 1.the zero is accidental.i shall edit my post.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

I am going to bring it down here:

-1 and 1 have no definition for them. You want it like that?

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

yes,that's right.it's easier to find a formula for that one that for the one where -1 and 1 are included.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

I have the graph looking like this:

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

that's exactly it.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

I am not seeing how to get those line segments into one form.

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

found it:The function

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

Isn't that a 3D plot?

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

i don't know how you got 3D.it's the graph of y=sgn(x+1)+sgn(x-1).

Here lies the reader who will never open this book. He is forever dead.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 83,058

Over there it is written as y sgn(x+1)+sgn(x-1).

Also that equation has a value at 1 and -1. Your piecewise does not.

I have the result, but I do not yet know how to get it.

All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 14,885

hi bobbym

i don't know if you know,but sgn function is not defined at 0.

Here lies the reader who will never open this book. He is forever dead.

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