Question

A = {1, 3, 5, 7, 9}
B = {2, 4, 6, 8, 10}
C = {1, 5, 6, 7, 9}
A ∪ B=

Answer 1

(1,2,3,4,5,6,7,8,9,10)

Answer 2

Write all the elements without repetition of any element.. Union means to combine all the elements present in all sets without repetition of any element..

Answer 3

∅
integers between 1 and 10
integers from 1 to 10 inclusive

Answer 4

Mathematica provides the Union function.
Refer to the attachment.
A, B and C are written in lower case. Upper case, willy nilly characters can cause problems with Mathematica.