Question

In: Advanced Math

2.2.6. Let S be a subset of a group G, and let S^-1 denote {s^-1: s...

2.2.6. Let S be a subset of a group G, and let S^-1 denote {s^-1: s ∈ S}.
Show that 〈S^-1〉 = 〈S 〉. In particular, for a ∈ G, 〈a〉 = 〈a^-1〉, so also
o(a) =o(a^-1)

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