Melody

with the $$\div$$ button

If you are doing calculations with mixed numerals it is best to put them in brackets like $$(3+1\div 2)$$

sounds good to me.

I hadn't finished my post - I got side tracked.  I must have published it unfinished. 

$$^4C_0 = \frac{4!}{(4-0)!0!}=\frac{4!}{4!}=1$$

You should know what y=cosx looks like

That is your starting point

$$y=4cos(n\theta)+1

the amplitude is 4

The period is 2\pi/n

\mbox{ The 1 on the end mean that the whole graph is raised 1 unit }

\mbox{ so instead of it being centred on the x axis (y=0) it is centred on y=1}$$

Chris, how are you entering attachments - are they straight off the net?

e is just a number   

$${{\mathtt{e}}}^{{\mathtt{1}}} = {\mathtt{2.718\: \!281\: \!828\: \!459\: \!045\: \!2}}$$

you do not need to know what e^8 is to work out e^3

just do it on a calculator.

You should look here

0! = 1 (By definition)

26P26 = 26!/(26-26)! = 26! This is how many ways you can order 26 items.

The answer is 26! ways.

If you are entering mixed numeral put them in brackets, for example

(2+3/4)-(9+7/8)