Solution (source code)

= Solution

The <Bolzano-Weierstrass theorem> states that every <bounded sequence> of real numbers has a <convergent subsequence>.

Condition (i) is insufficient because the allowed limit may be zero. For example, $a_n=1/n$ is nonzero and converges to zero, whereas $1/a_n=n$ does not converge in $\mathbb R$.