Math 170A Name: Ethan Aguirre
Spring 2024 – Worksheet 5 Directions
: Multiple choice. Each problem has only one correct answer. Use the area directly below to write your answer of A, B, C, etc. in the space provided next to the
problem number. Page one: 1. B 2. E 3. B 4. D 5. B Page two: 6. 7. F 8. D 9. B 10. A 1.
Which of the following represents the set {𝑥 ∈ ℝ | 5 < 𝑥 ≤ 8}
? (5,8]
A.
(3,8) ∩ [4, 7]
C. [0,8] ∩ (5,9]
B.
(5,8] ∩ [4, 7]
D. [0,8] ∩ [5,9]
A. [−1,7)
C. (−1,7)
B. (−1,7]
D. [−1,7]
2.
Which of the following represents the set ℤ ∩ [4,9)
? A.
[2,5)
C. [2,5]
E. {4,5,6,7,8,9}
G. ℤ
B.
{2,5}
D. [2,4] F. {4,5,6,7,8}
H. ℝ
3.
Which of the following represents the set ℝ − [7, ∞)
? A. (−∞, 7]
B. (−∞, 7)
C. (−∞, 6]
D. (−∞, 6)
4.
Which of the following represents the set ℝ − {4}
? A.
(−∞, 4) ∩ (4, ∞)
C. (−∞, 4] ∪ [4, ∞)
E. {… ,1,2,3,5,6,7, … }
B.
(−∞, 4] ∩ [4, ∞)
D. (−∞, 4) ∪ (4, ∞)
F. ℝ ∩ {4}
5.
Let the universal set be all real numbers. Let 𝑋 = {𝑥 ∈ ℝ | 𝑥 < −1 or 𝑥 ≥ 7}
. Find 𝑋̅
.
