MAT134Y5 Lecture Notes - Lecture 1: Real Number, Square Root, Solution Set
Document Summary
Lecture 01: real numbers and the real line. Real numbers: any number on the number line (integer, positive, negative, fraction, decimal) The square root of 2 and pi cannot be written as fractions. There are no holes on the number line. A = {1, 2, 3, } , b = {1, 1/2, 1/3, 1/4, } , c = {x|x > 0} Open interval: (a,b) = {x|a < x < b} Every number in between the end points (not including the end point values). Closed interval: [a,b] = {x|a < x < b} Every number in between the end points (including the end point values). Half-open/half-closed interval: [a,b) = {x|a < x < b} One end point is included, one end point isn"t included. Closed ray: [a, infinite) = {x|x > a} Every number after a (including a) is included. Open ray: (-infinite, b) = {x|x < b} Every number before b (excluding b) is included.
