Assuming you want to "simplify" this
(16^-2/4^4)^-1
1/(16^-2/4^4) Negative one power is reciprocal
(16^-2 / 4^4) (16^-2) = 1/(16^2) = 1/256 4^4 = 256
(1/256)/(256) = 1/(256^2) = 1/(65536)
Put it all together 1/(1/(65536) = 65536
Remember, x^-1 = 1/x x^-2 = 1/(x^2) and so on and (1/x)/x = x^2 and 1(1/x) = x
