Multiplication with same base:
$ a^m * a^n = a^{m+n} $
Multiplication with different base but same powers:
$ a^m * b^m = (a*b)^m $
Multiplication with different bases and different powers:
$ a^m*b^n = (a^m)*(b^n) $
When the exponent is a logarithm:
$ \exp\big\{\ln(a^b) \big\}=a^b $