course: Foundations of Higher Math Let . Give an example of a relation on A that is reflexive and transitive, but not symmetric. My question is, does my relation have to include all of the pairs to be reflexive? For example, say my relation is .
Follow Math Help Forum on Facebook and Google+
Originally Posted by MadSoulz course: Foundations of Higher Math Let . Give an example of a relation on A that is reflexive and transitive, but not symmetric. My question is, does my relation have to include all of the pairs to be reflexive? For example, say my relation is . Any reflexive relation on must contain as a subset.
Originally Posted by Plato Any reflexive relation on must contain as a subset. Perhaps my professor made a mistake in class. We had and said that was a reflexive relation.
Originally Posted by MadSoulz Perhaps my professor made a mistake in class. We had and said that was a reflexive relation. Are you sure you heard correctly? R is a reflexive relation on {1, 2} but not on {1, 2, 3}.
Originally Posted by HallsofIvy Are you sure you heard correctly? R is a reflexive relation on {1, 2} but not on {1, 2, 3}. Yes, he wrote the following table on the board then filled it in himself. was the only one that had an 'X' for reflexive.
Originally Posted by HallsofIvy Are you sure you heard correctly? R is a reflexive relation on {1, 2} but not on {1, 2, 3}. Here's the entire Powerpoint slide
Originally Posted by MadSoulz was the only one that had an 'X' for reflexive. is not even close to being reflexive: it does not contain a single pair from the diagonal.
Originally Posted by emakarov is not even close to being reflexive: it does not contain a single pair from the diagonal. Sorry EDIT: was the only one that had an 'X' for *not* reflexive.
was the only relation that was not reflexive. Forgive my earlier failed explanation
Originally Posted by MadSoulz was the only one that had an 'X' for *not* reflexive. Actually I suspected that was the case is the only one in the list that is irreflexive: i.e. I wonder if that is what your instructor meant?
Originally Posted by Plato Actually I suspected that was the case is the only one in the list that is irreflexive: i.e. I wonder if that is what your instructor meant? Perhaps. I'll have to ask him on Monday. He doesn't answer emails on weekends.
Thanks to you all for your time.
View Tag Cloud