Recent content by cubicmonkey

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    Undergrad Graphing Cartesian Products and Unions: Set Theory Sketches

    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]?
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    Undergrad Graphing Cartesian Products and Unions: Set Theory Sketches

    ([0,1] U {2}) For example what would this look like?
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    Undergrad Graphing Cartesian Products and Unions: Set Theory Sketches

    Thanks, DODO that was what I suspected for part a, but parts b and c still mystify me.
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    Undergrad Graphing Cartesian Products and Unions: Set Theory Sketches

    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...
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    Undergrad Is 3 Divisible by n if 3 is Divisible by n^2?

    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?
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    Undergrad Is 3 Divisible by n if 3 is Divisible by n^2?

    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.