Set Theory Questions 262693
1. **State the problem:** We are given multiple set theory questions involving membership, types of sets, set notation, and set operations.
2. **Membership statements (True/False):**
a. a \in A
b. x \in A
c. b \in A
d. e \in A
e. c \in A
f. Set A is finite.
To determine truth values, we need the definition of set A, which is not provided. So these cannot be answered without more info.
3. **Types of sets:**
a. N = \{1,2,3,4,\ldots\} is an infinite set because natural numbers continue indefinitely.
b. A = \emptyset is a null set because it contains no elements.
c. 5 \in \{3,8,9,14\} is False because 5 is not in the set.
d. x = 4 \cdot 3 + 3 \cdot 1 = 12 + 3 = 15 \in \{x : x \text{ is an integer}\} is True because 15 is an integer.
4. **Write sets in roster form:**
a. A = \{1,2,3,4,5,6,7,8,9,10\}
b. B = \{w,x,y,z\}
c. C = \{11,13,15,17,19,21,23\}
d. D = \{2,4,6,8,10\}
e. E = \{12,14,15,16,18\} (five non-prime numbers > 10)
f. F = \{42,43,44,45,46,47,48,49\}
g. G = \{2,3,5,7,11,13,17,19,23,29\}
h. H = \{April, August\}
i. I = \{1,3,5,7,9,11,13,15,17,19\}
5. **Set operations:**
Given M = \{1,3,5,7,9,11,13,15,17,19\}, N = \{3,6,9,11,13\}
a. M \cap N = \{3,9,11,13\}
b. M \cup N = \{1,3,5,6,7,9,11,13,15,17,19\}
6. Given P = natural numbers < 50, Q = natural numbers divisible by 5, R = even numbers 2 to 10:
a. P \cap Q = \{5,10,15,20,25,30,35,40,45\}
b. P \cap R = \{2,4,6,8,10\}
c. Q \cap R = \{10\}
d. P \cap Q \cap R = \{10\}
e. (P \cup R) \cap Q = Q = \{5,10,15,20,25,30,35,40,45\}
f. (P \cap Q) \cup R = \{2,4,5,6,8,10,15,20,25,30,35,40,45\}
7. Given e = \{2,4,6,8,10,12\}, A = \{2,6,10,12\}, B = \{4,8\}, C = \{2,4,8,10\}:
a. A' = e \setminus A = \{4,8\}
b. B' = e \setminus B = \{2,6,10,12\}
c. C' = e \setminus C = \{6,12\}
d. A' \cup B' = \{2,4,6,8,10,12\} = e
e. B' \cap C' = \{6,12\}
f. C' \cap A' = \emptyset
g. A \cup B' = \{2,4,6,8,10,12\} = e
h. (A \cup B)' = e \setminus (A \cup B) = e \setminus e = \emptyset
i. A \cap A' = \emptyset
j. A' \cap C = \{4,8\} \cap \{2,4,8,10\} = \{4,8\}
8. Given e = \{1,2,3,\ldots,10\}, A = \{1,2,3,4,5\}, B = \{1,2,6,7\}, C = \{3,5\}:
a. n(A \cap B) = n(\{1,2\}) = 2
b. n(B \cap C) = n(\emptyset) = 0
c. n(A \cup B) = n(\{1,2,3,4,5,6,7\}) = 7
d. n((A \cap B)') = n(e \setminus \{1,2\}) = 8
e. n((B \cap C)') = n(e \setminus \emptyset) = 10
f. n((A \cup B)') = n(e \setminus \{1,2,3,4,5,6,7\}) = 3
9. **Venn diagram:** The problem requests a Venn diagram with sets A, B, C showing intersections. This is a conceptual visualization of the above set operations.
Final answers are provided above for each question.