Solution
= Solution
\b[False.] The proper <subgroup> $2\mathbb Z\times2\mathbb Z$ of $\mathbb Z^2$ is isomorphic to $\mathbb Z^2$ and is not cyclic.
= Solution
\b[False.] The proper <subgroup> $2\mathbb Z\times2\mathbb Z$ of $\mathbb Z^2$ is isomorphic to $\mathbb Z^2$ and is not cyclic.