Solution
= Solution
<Liouville approximation theorem> states that if $\alpha$ is a real <algebraic number> of degree $d\geq2$, then there is a constant $c(\alpha)>0$ such that
$$
\left|\alpha-\frac pq\right|>\frac{c(\alpha)}{q^d}
$$
for every rational $p/q$ with $q>0$. The strict inequality may be replaced by a non-strict one after changing the constant.