Identify the empty set, the singleton set and the pair set.
C={x:x2=25,x∈N}
The given set-builder form is C={x:x2=25,x∈N}
In the set C, x2=25 and x∈N
x2-25=0
x-5x+5=0
x=5 or x=-5
5∈N but -5∉N
The roster form of the given set-builder form is given below
C=5
nC=1 , the set C is a singleton set.
Hence, the given set C={x:x2=25,x∈N} is a singleton set.
Classify the given set as finite, infinite, empty or singleton set:
{ The set of students more than 3 m tall}
B={x:x2-9=0,x∈Z}
D={x:5x-4=0,x∈W}
A=0