Recent content by cubicmonkey

So I uploaded my guess at it. What do you think? Is (b) correct? Does ([0,1] U {2}) simply become [0,1,2], which could be read as [0,2]?

([0,1] U {2}) For example what would this look like?

Thanks, DODO that was what I suspected for part a, but parts b and c still mystify me.

So the book asks me to sketch out these graphs, and of course there are no examples. I was wondering how this is done. (a) [0,1] X [1, 2] // The X here stands for the Cartesian product. (b) ([0,1] U {2}) X [1,2] // How can I graph this? The U stands for Union and the X here stands for...

I think I understand what you're saying and that looks like a contrapositive proof, but you don't actually prove it. Could you elaborate?

I'm completely lost on this one. I need this to be able to solve that the square root of three is irrational. So it's a proof within a proof, but I like this way best. Please help me out. This is what I need to know how to prove. 3|n^2 implies 3|n where n is some integer.