Reductio ad absurdum
After showing that a given hypothesis leads to a false statement, algebraically, for example, is it necessary to point out the contradiction or is it sufficient to end the proof at that point? I handed in an assignment recently and the marker wrote in that I had to put in some sort of statement indicating that a contradiction had been reached, but I didn't lose any marks.
It's like I always say - people find English easier to read than Mathematics... So I would give the explanation at the end.
I think the marker's right, in particular with involved proof. Do indicate always where the contradiction has been reached and what's been contradicted.
Originally Posted by Noxide
If you want to be really preicse, then you should finish with something like "This contradicts the assumption that..."