(3^-2e^4)^-1
[bracket three to the power of negative 2. 'e' to the power of 4, close bracket, to the power of negative 1]
(3^-2e^4)^-1 = (1/9 * e^4)^-1
= (e^4/9)^-1 = 1/(e^4/9) = 9/e^4
[bracket three to the power of negative 2. 'e' to the power of 4, close bracket, to the power of negative 1]
= (e^4/9)^-1 = 1/(e^4/9) = 9/e^4