PowerExpand

PowerExpand[expr] expands all powers of products and powers.

PowerExpand[expr, {x1, x2, ...}] expands only with respect to the variables xi.

Examples

Expand a power of a product:

PowerExpand[(a b)^n]
(* a^n b^n *)

Expand a logarithm:

PowerExpand[Log[x y]]
(* Log[x] + Log[y] *)

Please visit the official Wolfram Language Reference for more details.