TAOCP 1.2.2 Exercise 3
By Eq.
Section 1.2.2: Numbers, Powers, and Logarithms
Exercise 3. [02] What is $(-3)^{-3}$?
Verified: yes
Solve time: 31s
By Eq. (4),
$(-3)^{-3} = \frac{(-3)^{-2}}{-3} = \frac{(-3)^{-1}}{(-3)^2} = \frac{1}{(-3)^3}.$
Since
$(-3)^3 = (-3)(-3)(-3) = 9(-3) = -27,$
we obtain
$(-3)^{-3} = \frac{1}{-27} = -\frac{1}{27}.$
Therefore the answer is
$\boxed{-\frac{1}{27}}.$