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Let $G$ be the group given by the following presentation $$ G=\langle x,y:x^3=y^2=1\rangle $$ I want to find $Z(G)$. I notice that $\langle x\rangle\cap\langle y\rangle=\{1\}$, Does that means that $Z(G)=\{1\}$?

Nic
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boaz
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1 Answers1

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There is no reason why the intersection being trivial would imply a trivial center. In the dihedral group of order $8$, the group is generated by a rotation and a reflection, the cyclic subgroups they generate have trivial intersection, yet the center is not trivial.

The group $G$ is isomorphic to $C_3*C_2$, the free product of a cyclic group of order $3$ and one of order $2$. Free products of nontrivial groups are centerless, so $G$ is centerless.

Arturo Magidin
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