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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

hi guys

tell me what you think of these:

1)two horizontal rays at heights 3 and 1:

y=2+sgn(x)

this can be generalized to two horizontal rays of heights a and b with the formula being:

2)two parallel non-horizontal rays at heights 1 and -1:

y=x+sgn(x)

this can be generalized to two parallel non-horizontal rays at heights a and b with the formula:

but can also be generalized to two **non**-parallel non-horizontal rays at heights a and b with the formula:

3)i have also find a way to plot two parallel lines(horizontal or vertical),but unfortunately wolfram won't plot this function.

for two vertical lines there are 3 different formulas depending where we want the lines to be.i will give the formula for when the two lines are on the right of the y-axis:

*Last edited by anonimnystefy (2012-02-19 02:11:45)*

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

any feedback?

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: 86,665

I can not see anything, can you fix the tags?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

all fixed up

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: 86,665

Hi;

Sometimes it is convenient to use piecewise functions.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

yes,but i looked for ways to do it with only one function.

is there to merge a three-part piecewise function into one?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

Hi anonimnystefy;

What is the piecewise function?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

e.g.:

f(x)={(-1 when x<1,0 when x∈(-1,1),1 when x>1)

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

I can not see any of those images so I am having trouble understanding what you already did.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

i put in some links instead of pictures.it should be fine now

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

I am still only getting Alpha' s site and that whirring thing.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

what whirring thing?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

The symbol for computation is running.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

it's working fine for me.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

Hi anonimnystefy;

Sorry, I am not getting anything.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

hi bobbym

i don't know what to do,but you could try entering that into W|A yourself.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

Yes, I have done that. I can now see it all.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

and?

btw,i successfully installed wxMaxima.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

That is good but you should have asked me first.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

why?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,665

I would have suggested Geogebra, it comes with Maxima and with latexing capabilities.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

hi bobbym

i think i have Geogebra on my desktop computer,and it's very good.i like that i'm able to give out commands instead of drawing everything "by hand" although i think that the latter is better.

but anyway Maxima by itself is not bad at all except for some few minor incapabilities.what i would like to do is find a way to solve recursions and then use the function that i get a a solution as a function on its own.

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: 86,665

I do not know what Maxima's capabilities for solving recurrences is offhand. They are solved by two methods, generating functions and the auxiliary polynomial.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,523

i know them both.for some of them i like GFs more,but for some too hard i like using the AP.

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: 86,665

Generally, like DE's only some of them can be solved for.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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