4. Sets
A set is an unordered collection of distinct objects.
When we list elements within a set, we use these curly brackets { }
and separate each element in the list with commas.
When 𝑥 is an element of the set 𝐴,
then We say that 𝑥 is belong to 𝐴 or 𝒙 ∈ 𝑨
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5. Sets
• A subset would be a selection of these elements
• The universal set, ξ, is the list of every element that there is available to choose
from.
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6. Sets of Numbers
• Digits: {0,1,2,3,4,5,6,7,8,9}
• Binary: {0,1}
• Set of Even Numbers: {0,2,4,6,7,…}
• Set of Odd Numbers: {1,3,5,7,9,…}
• Set of Prime Numbers: {2,3,5,7,11,13,…}
(Numbers that is divisible by 1 and itself)
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10. Comparison Sets
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• When sets A and B have exactly the same members we write 𝑨 = 𝑩.
• When all the elements of 𝐴 are also members of 𝐵 we say that 𝐴 is a subset of 𝐵, and write 𝑨
⊆ 𝑩.
• Two alternative ways of saying the same thing are that 𝐴 is included in 𝐵 or that 𝐵 is a superset
of 𝐴, written 𝑩 ⊇ 𝑨.
