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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi Amarylli$;

Like this:

**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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**Au101****Member**- Registered: 2010-12-01
- Posts: 286

Can I offer a suggestion regarding the typesetting of matrices. The array environment is very useful, however, there is a dedicated environment which some may find useful, simply use:

\begin{φmatrix}

\end{φmatrix}

Where φ is a variable. pmatrix will produce a matrix with parentheses, or standard brackets, bmatrix one with square brackets, Bmatrix one with braces, or curly brackets, vmatrix one with straight lines and Vmatrix one with double straight lines. Simply using matrix will create a simple array, with no brackets of any kind. As before entries are separated with & and \\ will drop a line. Note adding \\[φpt] will leave a gap of φ point. Seeing as LaTeX is, by default, usually 12pt, I suggest \\[12pt].

To exemplify

\begin{bmatrix}

a & b \\

c & d

\end{bmatrix}

Produces

\begin{vmatrix}

a & b \\

c & d

\end{vmatrix}

Produces

etc.

*Last edited by Au101 (2010-12-17 13:58:46)*

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**loida****Member**- Registered: 2009-11-12
- Posts: 32

hi there.. does anybody know how do i get characterictic function (not \chi , i need symbol with 1 ) in latex? i can't find it..

*Last edited by loida (2011-10-09 02:00:29)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

**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: 15,525

hi loida

is that it?

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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**loida****Member**- Registered: 2009-11-12
- Posts: 32

great.. thank you bobbym and anonimnystefy

it's

\usepackage{ bbold }

\mathbb{1}

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi loida;

We cannot use packages in this latex.

Is that essentially the same symbol?

**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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**loida****Member**- Registered: 2009-11-12
- Posts: 32

no..i don't how to get it here..

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

That is what I thought. How did you get the answer then?

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**loida****Member**- Registered: 2009-11-12
- Posts: 32

your site helped me..i just drew

*Last edited by loida (2011-10-09 02:22:02)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi;

Okay, very good, that site is useful.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**loida****Member**- Registered: 2009-11-12
- Posts: 32

yes, site is wonderful..thank you very much for sharing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Your welcome.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**Au101****Member**- Registered: 2010-12-01
- Posts: 286

Hi, yeah, I won't go into the details, but basically LaTeX is a mark-up language, and they way mark-up works - as you will probably have realised - is that if you want your text to appear in a certain way - such as to be in bold face - then you 'mark up' the text. i.e. you use special sequences of characters (called control sequences) to induce an effect (e.g. \textbf{Hi} makes Hi become **Hi**. textbf is the control sequence and the \ is known as the escape character, which escapes the control sequence. This means that the control sequence is interpreted as a command, rather than just normal text.) Anyway, I probably could have explained that better, but it's not very important, so don't worry if you didn't follow it. The main point is that these control sequences are interpreted by a renderer, which creates the final document. Now, the renderer already 'knows' the basic commands, such as \frac{x}{y}, however, we can also write packages which extend LaTeX beyond these very basic functions. Now, bbold is an example of a package which was written to give LaTeX more functionality. If our renderer doesn't know how to interpret \mathbb{1} in the way we want it to, then we have to load that package, and then the renderer will use the information contained in that package to interpret our control sequence. Otherwise, it will use the standard interpretation. IIn this case, the mathsisfun renderer does know the standard interpretation (bobbym's symbol) but not the interpretation you want. If you ever use your own renderer and write LaTeX for yourself outside of this forum, then you can use the bbold package and extend your own LaTeX capabilities. However, the mathsisfun forum (for very good reasons, mostly simplicity but also to prevent abuse) does not support the loading of extra packages, so we have to make do with the functionality we have.

*Last edited by Au101 (2011-10-09 03:56:28)*

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**loida****Member**- Registered: 2009-11-12
- Posts: 32

hey.. how do i put .gif in latex?

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**Au101****Member**- Registered: 2010-12-01
- Posts: 286

Hi

Is that on the forums or at home? On the forums, you cannot insert any pictures in LaTeX, you must use the standard bbcode. At home, if you are using graphicx, the supported image formats really depend on the renderer which you are using, however, I do not know of any renderer which supports .gif. pdflatex - the most common and, indeed, useful one, will only support .jpg, .png and .pdf, to the best of my knowledge. It may have expanded its abilities by now, or there may be a package which can do something clever and allow .gif files to be inserted (almost certainly by converting them to .jpg/.png for you) but I think that this is quite unlikely. Instead you should use one of these formats. Indeed, if you are using it for a diagram, then a vector image in .pdf format will definitely have a much much better effect.

*Last edited by Au101 (2011-10-09 19:02:41)*

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**loida****Member**- Registered: 2009-11-12
- Posts: 32

thank you Au..

I need it at home.. can you give me the code?

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**Au101****Member**- Registered: 2010-12-01
- Posts: 286

Hi Ioida

In your preamble write

\usepackage{graphicx}

Graphicx will probably look for the picture in whichever directory the .tex file is in, but it's best to specify the graphicspath - especially if your picture is somewhere else on the system, in which case it won't find it, so write underneath that (yes, two braces, it works better, apparently):

\graphicspath{{filepath}}

Then, wherever you want the picture:

\includegraphics{filename}

It should not be necessary to include the extension. You can also scale the picture using

\includegraphics[scale=x]{filename}

Give x as a decimal, e.g. 0.5 or 1.8.

You can also use the figure environment if you want captions. There is a lot of information about this in the LaTeX manual (http://en.wikibooks.org/wiki/LaTeX). There are also dedicated forums for LaTeX queries, and - indeed - TeX queries in general, and I suggest that for general TeX questions you go there. Not that I'm not completely happy to help, but you're much more likely to find your answer. Also, please remember that this won't work for .gif, I don't think. You should be using .jpg, .png or .pdf.

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**loida****Member**- Registered: 2009-11-12
- Posts: 32

awesome!!! thank you!

i've converted it to .jpg

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**sassygirl****Member**- Registered: 2011-10-30
- Posts: 3

UH this is confusing this site is just wow like going down and down to comment and then when i comment i forget what to say or what the topic is about

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi sassygirl;

Welcome to the forum. What is the problem?

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**djsakds****Guest**

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi;

Welcome to the forum!

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: 15,525

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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**hi2****Guest**

thats cool

2x