[tex]$Q H 7:$[/tex] If [tex]$U =\{29,30,31, \ldots ,45\}$[/tex], list the complements of the following sets.

a) [tex]$A=\{32,33,37,39,42,44\}$[/tex]

b) [tex]$B=\{$[/tex] multiples of 4 [tex]$\}$[/tex]

c) [tex]$C = \{$[/tex] non-prime numbers [tex]$\}$[/tex]



Answer :

Sure, let's work through each part of the question step by step to find the complements of the given sets.

Part (a): Complement of [tex]\( A \)[/tex]

Given:
- The universal set [tex]\( U = \{29, 30, 31, \ldots, 45\} \)[/tex].
- The set [tex]\( A = \{32, 33, 37, 39, 42, 44\} \)[/tex].

To find the complement of [tex]\( A \)[/tex] (denoted as [tex]\( A^c \)[/tex]), we need to include all elements in [tex]\( U \)[/tex] that are not in [tex]\( A \)[/tex].

The elements in [tex]\( U \)[/tex] are: [tex]\( 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45 \)[/tex].

Removing the elements of [tex]\( A \)[/tex] from [tex]\( U \)[/tex]:

[tex]\[ A^c = U - A = \{29, 30, 31, 34, 35, 36, 38, 40, 41, 43, 45\} \][/tex]

Part (b): Complement of [tex]\( B \)[/tex]

Given:
- The set [tex]\( B = \{x \in U : x \text{ is a multiple of 4} \}\)[/tex].

Multiples of 4 within the range of [tex]\( U \)[/tex] are: [tex]\( 32, 36, 40, 44 \)[/tex].

To find the complement of [tex]\( B \)[/tex] (denoted as [tex]\( B^c \)[/tex]), we include all elements in [tex]\( U \)[/tex] that are not multiples of 4.

[tex]\[ B^c = U - B = \{29, 30, 31, 33, 34, 35, 37, 38, 39, 41, 42, 43, 45\} \][/tex]

Part (c): Complement of [tex]\( C \)[/tex]

Given:
- The set [tex]\( C \)[/tex] includes non-prime numbers in [tex]\( U \)[/tex].

Non-prime numbers within the range of [tex]\( U \)[/tex] are: [tex]\( 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45 \)[/tex].

To find the complement of [tex]\( C \)[/tex] (denoted as [tex]\( C^c \)[/tex]), we include all elements in [tex]\( U \)[/tex] that are prime numbers.

The prime numbers in the range [tex]\( U \)[/tex] are: [tex]\( 29, 31, 37, 41, 43 \)[/tex].

[tex]\[ C^c = U - C = \{29, 31, 37, 41, 43\} \][/tex]

Summary of Complements:

- [tex]\( A^c = \{34, 35, 36, 38, 40, 41, 43, 45, 29, 30, 31\}\)[/tex]
- [tex]\( B^c = \{33, 34, 35, 37, 38, 39, 41, 42, 43, 45, 29, 30, 31\} \)[/tex]
- [tex]\( C^c = \{37, 41, 43, 29, 31\} \)[/tex]

Thus, those are the complements for each of the sets [tex]\( A \)[/tex], [tex]\( B \)[/tex], and [tex]\( C \)[/tex].