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If $(G,*)$ is a group and $a^{-1}=a, \forall a \in G$ then $G$ is abelian . Is it true or false and why?

Stefan4024
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  • Hint: $$ab=(ab)^{-1}=b^{-1}a^{-1}$$ – Prasun Biswas Nov 15 '17 at 14:03
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    Welcome to stackexchange. Your question has been downvoted because you didn't provide any information about how you got started and where you were stuck. You did get answers anyway - but next time please ask your question better. Note too that someone edited to improve the math formatting. Do that yourself next time. – Ethan Bolker Nov 15 '17 at 14:04

2 Answers2

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HINT: Take $a = xy$ for any $x,y \in G$

Stefan4024
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It is true. We have $abab=e$ then $ab=b^{-1}a^{-1}$ but $b^{-1}a^{-1}=ba$

GhD
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