Types of sets (finite, infinite, empty, singleton)
Sets, relations and functions · Mathematics
Study notes
Q: Classify: (a) {x : x^2 = 4, x natural} (b) {x : x^2 = -1, x real} (c) multiples of 5. (a) x = 2 only: {2} - singleton, finite. (b) No real solution: {} - empty set. (c) {5, 10, 15, ...} - infinite.