To insert a new equation in a Google Docs file, like e.g. the one in Attachment 4 click Insert -> Equation
You will now be able to see the tool bar with a button "New equation", as shown in the first attachment.
Click this button and you are able to type your equation. Once you need something like subscripted letter it gets a little more tricky. Now you have to choose the type of variable you need from the drop down "Math operations" as shown in attachment 2, but it won't just insert this variable you actually have to type the letter you want in normal size first, then use the right arrow key to let the cursor know that you would now like to type a subscripted letter and then use the arrow key again to be able to type normally again. Attachment 3 shows a rightly placed cursor.
The same applies, e.g. for divisions
With Google docs, various common documents (Text documents very similar to MS Word, Tables very similar to MS Excel, Presentations very similar to MS Powerpoint, paintings, formulas and more) can be created and edited in the best collaborative manner:
- One can always see the cursors of all the other people editing the document at the same time, so you can always see on what part your team members are working on
- The document is automatically saved after every single change
- A chat function is included
- Existing documents (Word, Excel, Powerpoint, etc.) can be imported
- Documents can be downloaded in plenty of formats and so e.g. edited offline. For example, a text document can be downloaded as ODT, PDF, RTF, Text, Word or HTML.
- One can also work offline, as soon as the computer is online again, the document is being updated and saved.