Question

f(x) = 6 ln (1/e^9)

Answer 1

as a first step, re-write 1/e^9 as \( e^{-9}\)

Answer 2

then use the rule ln(e^a)= a

Answer 3

a function of x without x.... what are you trying to do? find integral? derivative?
if you want to simplify the expression then ye, what phi said