Answer:
a) False. b) False. c) No, it's Rational. d) pi=355/113 e) 5i (for Complex Set of Numbers)
Step-by-step explanation:
a) Since there is the empty set. And an axiom assures us the existence of this Set. "There is a set such no element belongs to it"
∅ has no elements.
b) A perfect number is a positive integer equals to the sum of proper divisions
The smallest is 6. Since the proper divisors of 6={3,2,1}. 6=1+2+3
28 is a perfect number, but not the smallest. It is perfect since
28 proper divisors={14,7,4,2} 28=1+2+3+4+5+6+7
c) No, An Irrational number cannot be written as a fraction a/b where "a" and "b" are integers. 1.5 is a rational one, since 3/2 =1.5
d)
[tex]\pi[/tex]=22/7 -1/791= 355/113
e) Not for Real Numbers, since it is not defined for Real numbers. But for the set of Complex 5i