Let H1, H2, H3, . . . be a sequence of subgroups of a
Chapter 4, Problem 32SE(choose chapter or problem)
Problem 32SE
Let H1, H2, H3, . . . be a sequence of subgroups of a group with the property that H1 ⊆ H2 ⊆H3 . . . . Prove that the union of the sequence is a subgroup.
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