ECON 1530 Lecture 9: ECON 1530 Lecture 9 Notes – Double Inequalities, Intervals and Absolute Values and Absolute Value

• School: York University
• Department: Economics
• Course: ECON 1530
• Professor: John Paul Rilstone

Document Summary

Econ 1530 lecture 9 notes double inequalities, intervals and absolute values and absolute. Introduction: two inequalities that are valid simultaneously are often written as a double inequality. C (cid:1095) (cid:1008)(cid:1009): di(cid:448)idi(cid:374)g these i(cid:374)e(cid:395)ualities (cid:271)(cid:455) (cid:1013)/(cid:1009) (cid:894)o(cid:396) (cid:373)ultipl(cid:455)i(cid:374)g (cid:271)(cid:455) (cid:1009)/(cid:1013)(cid:895) (cid:455)ields (cid:1005)(cid:1004) (cid:1095) c (cid:1095, the te(cid:373)pe(cid:396)atu(cid:396)e thus (cid:448)a(cid:396)ied (cid:271)et(cid:449)ee(cid:374) (cid:1005)(cid:1004) c a(cid:374)d (cid:1006)(cid:1009) c. Intervals and absolute values: let a and b be any two numbers on the real line, then we call the set of all numbers that lie between a and b an interval. Absolute value: let a be a real number and imagine its position on the real line, the distance between a and 0 is called the absolute value of a. If a is positive or 0, then the absolute value is the number a itself. If a is a positive number and |x| < a, then the distance from x to 0 is less than a. equal to a.