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# Guide to posting in the Maths forum - PLEASE READ BEFORE POSTING!!!

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1. First off, I'd like to welcome you to the Maths Forum!

Before you post your own questions or give help to others there are few important things you should be aware of. A lot of this has until now been quite unspoken guidelines among the people who are well known in the maths subforum.

Even before posting a question, make sure that you have made a real effort to answer it yourself. You will only really learn from the help on offer if you have already spent some time on the question - otherwise, the help tends to go 'in one ear and out the other'.

When you do post, try to post your question clearly, with no inaccuracies, and nothing relevant missed out. Do use the preview button, and try to decide if you've given all the information required.

Secondly, tell people what you have already tried. If at all possible, you should post your working. People are not going to just post an answer for you - they are going to try to help you work the answer out. And they can't help you if you don't post working.

Thirdly, try to remember that not everyone who posts here will be familiar with the exact details of the course you are studying. So try to state your exam board, syllabus, and anything else that might be useful. If possible, try to make the thread title reasonably descriptive, that way people can quickly decide which questions they can help with.

The key aim here is to show the original poster how they can answer the question. There is actually quite a lot of skill and experience involved in doing this well. For example, if they are stuck using a particular method, the ideal is to show them how to get that method to work, not to show them a solution using a completely different technique.

In general, the best approach is to give small 'nudges' in the right direction; in contrast, posting full solutions is frowned upon.

Try to remember that people posting here have widely differing experience levels and educational backgrounds. Just because someone has posted what you consider an extremely simple question, it doesn't give you any right to try to make them feel inferior about it.

By the same token, please try to use common sense when deciding if you can answer a question. If a thread has 15 detailed posts from people at university level with no resolution, it is somewhat unlikely someone studying AS maths will be able to help. That doesn't mean you can't try, but do take the time to read the other posts and check you really understand what's going on before posting anything.

On Formatting Mathematics on TSR (How to do equations like on TSR)

TSR uses a system called LaTeX for typesetting mathematics. There is a detailed guide about using LaTeX on TSR here. In general, it is fairly straightforward to use, although really complex formulae can take a lot of effort to get right.

Do I have to use LaTeX? No, and even those of us who know how to use it often don't bother. The most important thing is to make sure what you are posting is unambiguous. For example, if you post

x / x - 1,

it isn't clear whether you actually meant or . If you posted

x / (x-1)

then that would be fine (and doesn't require you to know LaTeX). For long formulae, it becomes very difficult to make them clear without ending up with an unreadable mass of brackets, at which point you probably should use LaTeX if you want anyone to actually go to the bother of helping you.

In the long run, it is well worth learning how to use LaTeX, but you don't have to, and it is probably better to move onto it gradually, rather than thinking you have to do everything in LaTeX.

On Posting Full Solutions

This is a thorny topic, which has probably caused more arguments than anything else on this forum. To make it perfectly clear, the consensus (and forum rule), is that posting of full solutions should be considered a last resort. If your first contribution to a thread is to post a full solution, the moderators are quite entitled to take action.

But what's wrong with full solutions? Posting a full solution means you're not letting the person asking the question see where they went wrong. As such, you're only telling them how to answer one particular question, rather than helping them understand how and why they went wrong.

Say for example you knew how to do one question, and in your exams there was a slightly different question that required a little more thought. Understanding why the method works will put you in a better position to tackle the question and that is why it is discouraged to post full solutions.

So when you're helping people in the maths forum, in general don't post full solutions. Help them yes and if they get stuck and ask for more help them some more. For more extensive discussion on the topic you might find it interesting to read this thread.

A Brief Introduction To LaTeX

If you don't want to look at the full article linked to above, opening the spoiler below will give you a brief introduction:

Spoiler:
Show
To use LaTeX on TSR you have to use special html like tags

$- This starts the line of LaTeX off$ - This ends the line of LaTeX

To get started in LaTeX you really only need the above and a few other things; as you progress through academia, the amount of LaTeX needed will increases naturally.

A lot of the symbols you can see on a keyboard can be used in LaTeX already without using special codes. For example

A Simple Equation

The code used to create this is as follows

$y = 6x - 5$

Notice that - and = can be used in the latex tags theres no need to learn anything for those symbols!

Fractions

The code used to create this is as follows

$y = \frac{6x}{5}$

\frac - This is the code used to denote a fraction
{}{} - In the first pair of curly brackets this is where you can type anything in the nominator. In the second pair of curly brackets is where you can type anything in the denominator

You should be able to see where the 6x and 5 go in the code above.

Indices

Often in maths its important to be able to show powers where the number is slightly above and to the right of the x or y or whatever variable you are using. Take the following examples

The code is

$y = x^2$

^ - This tells the LaTeX to make an indices after the x.

If you want a power of say (y+1) or (x+y+1) you need a curly bracket around it like so

The code is

$y = x^{x+1}$

Notice the curly bracket around x + 1. This is to tell LaTeX that the indice is x+1. Anything inside the bracket will be included in the indice.

If you want to put a fraction as a power like

Heres the code

$y = x^{\frac{3}{2}}$

Notice there's curly brackets around the fraction, this means that the fraction gets included into the power.

Again

^ - tells the LaTeX to make an indices after the x
\frac{3}{2} - This gives you a fraction
{} - The curly brackets around the fraction are used to show that the whole fraction is involved in the indices and not part of equation.

The Square Root

Often in mathematics you need to be able to show the square root of something. For example

Heres the code

$y = \sqrt{x^2+ax+b}$

\sqrt - This tells LaTeX that you want a square root
{} - The curly brackets are used to enclose what ever you want to be include in the square root. In this case

That is it! You should now know how to use LaTeX to write simple equations using fractions, indices and square roots.

To finish it off you can now use the LaTeX you have learnt to form the quadratic equation!

The code

$x = \frac{-b \pm \sqrt{b^2-4ac}}{2a}$

\frac{}{} - gives us the fraction we want
\pm - this is a symbol to show and plus and a minus
\sqrt{b^2-4ac} - This is to show the square root with b^2 - 4ac in it notice the curly brackets.

Notice also theres also a final set of curly brackets at the end of the nominator so that everything gets included into the top part of the fraction.

If you have any questions about LaTeX, how to properly setup a question or about posting in the maths forum. PM me and i will be happy to help.

TSR Maths society - often used for discussion of more interesting challenging problems, not for getting help with your homework!

Further LaTeX Links (Courtesy of Vector)

LaTeX Symbols

The Short LaTeX Reference Guide
Updated: February 9, 2007
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