Solution
= Solution
The <Big O notation> asserts an eventual uniform bound on the size of $f$ by a constant multiple of the size of $g$:
$$
\boxed{f(n)=O(g(n))\iff\exists C>0\ \exists n_0\ \forall n\geq n_0:\ |f(n)|\leq C|g(n)|.}
$$
The constants $C,n_0$ may depend on the two <functions> but cannot depend on $n$. Absolute values matter because the stated <functions> can be real-valued with either sign.