10.12.2023
Question 1: Let $A = \{1, 2, 3\}$ and $B = \{w, x, y, z\}$. How many onto functions $f:A \rightarrow B$ are possible?
(3 points)
A. 0
B. 3
C. 4
D. 12
Answer
A. 0Question 2: Let $A = \{1, 2, 3\}$ and $B = \{w, x, y, z\}$. Which one of the following functions from A to B are not onto?
(3 points)
A. $\{(1,x),(2,y),(3,z)\}$
B. $\{(2,x),(3,y),(1,z)\}$
C. $\{(3,y),(2,x),(1,x)\}$
D. $\{(3,z),(1,y),(2,x)\}$
Answer
C. $\{(3,y),(2,x),(1,x)\}$Question 3: Let $A = \{1, 2, 3\}$ and $B = \{w, x, y, z\}$. Which one of the following functions from A to B is not a 1-to-1 correspondence?
(3 points)
A. $\{(1,x),(2,y),(3,z)\}$
B. $\{(2,x),(3,y),(1,z)\}$
C. $\{(3,y),(2,x),(1,x)\}$
D. $\{(3,z),(1,y),(2,x)\}$