trying to be a mile wide AND a mile deep
This is an exam problem I gave once; you’ll need to know |A| is the size/number of elements of A. Let A and B be finite nonempty sets, and f a function from A to B. Fill one I, for injective (1-1), and one S, for surjective (onto), in each line of the following table […]
The three properties of relations learned first are reflexivity, symmetry, and transitivity. Reflexivity is an existence property; a possession property. If you contain this entire particular set of pairs, you’re reflexive. If not, then not. Symmetry and transitivity are implications; closure properties. Now some pairs don’t come for free – they require other pairs be […]
Let A = {1,2,3,4,5}. Define a function f from A to A that is also a transitive relation, but is not the identity function. Answer after the jump.