Answer:
Step-by-step explanation:
Given the elements in sets,
[tex]D=[/tex]{[tex]14,17,19[/tex]}
[tex]E=[/tex]{[tex]14,16,17,18[/tex]}
[tex]F=[/tex]{[tex]13,15,16,17,19[/tex]}
[tex]D[/tex]∪[tex]E[/tex] is asked to be found.
Now it is clear that [tex]F[/tex] is unnecessary for this question.
[tex]D[/tex]∪[tex]E[/tex]=[tex]D+E-(D[/tex]∩[tex]E)[/tex]
[tex]D[/tex]∪[tex]E[/tex]={14,17,19}+{14,16,17,18}-{14,17}
[tex]D[/tex]∪[tex]E[/tex]={14,16,17,18,19}