AsymptoticLessEqual

AsymptoticLessEqual[f, g, x -> x*] gives conditions for f(x) ⪯ g(x) or f(x) ∈ O(g(x)) as x -> x*.

AsymptoticLessEqual[f, g, {x1, ..., xn} -> {x1*, ..., xn*}] gives conditions for the multivariate case.

Examples

Check big-O notation:

AsymptoticLessEqual[x + Log[x], x, x -> Infinity]
(* True *)

Please visit the official Wolfram Language Reference for more details.