7. Classify each of the following as true or false. If false, tell why or give an example showing that it is not true.

Question

(a) For all sets A and B, A – B = B – A

(b) For all sets A,   A

(c) For all sets A, A  A  

(d) The set {r, s, t,. . ., z} is a finite set.

(e) No set can be equivalent to all of its subsets

Answer 1

1. Try to post your question in ISO-8859-1 encoding so everyone sees what the special characters are.

2. You can type certain characters related to sets as follows:
"& c u p ;" ∪
"& c a p ;" ∩
"& s u b ;" ⊂
"& i s i n ;" ∈
"& n o t i n ;" ∉
"& e m p t y ;" ∅
"& a n d ;" ∧
"& o r ;" ∨
Do not include the double quotes nor the intervening spaces.