English
If f and g are almost everywhere measurable, then x ↦ f(x)^g(x) is almost everywhere measurable.
Русский
Если f и g измеримы почти всюду, то x ↦ f(x)^g(x) измеримо почти всюду.
LaTeX
$$$\\text{AEMeasurable}(f) \\Rightarrow \\text{AEMeasurable}(g) \\Rightarrow \\text{AEMeasurable}(x \\mapsto f(x)^{\\,g(x)}).$$$
Lean4
@[aesop safe 20 apply (rule_sets := [Measurable]), fun_prop]
theorem pow (hf : AEMeasurable f μ) (hg : AEMeasurable g μ) : AEMeasurable (fun x => f x ^ g x) μ :=
measurable_pow.comp_aemeasurable (hf.prodMk hg)