Lecture 2: The Real Number System
The real number system is the set of real numbers with two
operations called addition and multiplication. If a, b R, then
the sum of a and b is a + b (where a and b are called addends
or terms ) and the product of a and b
Exercises on Sets and the Set of Real Numbers
1. TRUE OR FALSE.
(a) If A B = A, then B = A.
(b) Given 3 nonempty sets A, B , and C , if A = B and B = C , then A = C .
(c) For any two sets X and Y , if x Y and y X , then X and Y are disjoint
Discussion for 14 June 2013
I. Exercise on interval notation: Let the universal set be R, X be the half-open interval 3 , 5 ,
Y = cfw_x | 4 |x|, and Z be the interval (2, +). Find the following sets and express them in