Any of the laws a^maⁿ = a^m+n, a^m/aⁿ = a^m-n, (a^m)ⁿ = a^mn, (ab )ⁿ = aⁿbⁿ, (a /b )ⁿ = aⁿ/bⁿ; these laws are valid when m and n are any integers, or when a and b are positive and m and n are any real numbers. Also known as exponential law.