Answer:
[tex] n(A \cup B) = 10 \textsf{ including H}[/tex]
Step-by-step explanation:
The symbol [tex] n(A \cup B) [/tex] represents the cardinality or the number of elements in the union of sets A and B.
Set A = [tex]\{3, 7, H, 11, 15\} [/tex]
Set B = [tex]\{-1, 2, 3, 5, 7, 11, 13, 17\} [/tex]
The union of sets A and B, denoted as [tex] A \cup B [/tex], is the set of all elements that are in A, or in B, or in both.
[tex] A \cup B = \{ -1, 2, 3, 5, H, 7, 11, 13, 15, 17 \} [/tex]
Now, the cardinality [tex] n(A \cup B) [/tex] is the number of elements in the set [tex] A \cup B [/tex].
[tex] n(A \cup B) = 10 \textsf{ including H}[/tex]
Therefore, [tex] n(A \cup B) [/tex] is 10, meaning there are 10 elements in the union of sets A and B.
