Let $$\begin{array} { l }
U = \{ 1,2,3,4,5,6,7,8,9,10 \} \
A = \{ 3,5,7 \} \
B = \{ 5,8,9 \}
\end{array}$$ List all the members of the set. $A \cup B$
A) $\{ 3,5,7,8,9 \}$
B) $\{ 5,8,9 \}$
C) $\{ 3,5,7 \}$
D) $\{ 5 \}$
E) $\varnothing$

Question

Let $$\begin{array} { l } 
U = \{ 1,2,3,4,5,6,7,8,9,10 \} \
A = \{ 3,5,7 \} \
B = \{ 5,8,9 \}
\end{array}$$ List all the members of the set. $A \cup B$
A) $\{ 3,5,7,8,9 \}$
B) $\{ 5,8,9 \}$
C) $\{ 3,5,7 \}$
D) $\{ 5 \}$
E) $\varnothing$

Quizplus · Accepted Answer

The union of two sets, represented by the symbol $\cup$, is the set of all elements that are in either set. Therefore, $A \cup B$ consists of the elements that are in $A$, in $B$, or in both. These elements are $3, 5, 7, 8,$ and $9$, so the answer is $\{3,5,7,8,9\}$, which is choice $	extbf{(A)}$.

Let U={1,2,3,4,5,6,7,8,9,10}A={3,5,7}B={5,8,9}\begin{array} { l } U = \{ 1,2,3,4,5,6,7,8,9,10 \} \\A = \{ 3,5,7 \} \\B = \{ 5,8,9 \}\end{array}U={1,2,3,4,5,6,7,8,9,10}A={3,5,7}B={5,8,9}​

Let $\begin{array} { l } U = \{ 1,2,3,4,5,6,7,8,9,10 \} \\A = \{ 3,5,7 \} \\B = \{ 5,8,9 \}\end{array}$