Would be more easier to read if we had some brackets to make the expression less ambiguous. Otherwise, there's a bit of guess work involved.
Thank you Soroban.
My next challenge is to simplify the first product as you just wrote (I know I am on deep water):
I need to know step by step, which math rules are used etc. to get the final expressions.
Do you know any software, which are able to help me with this?
Or else I can keep you guys busy, like forever.