Answer:
-8
Step-by-step explanation:
We can write [tex]f(x)=\frac{8}{x}[/tex], or equivalently [tex]f(x)=8x^{-1}[/tex]. Using the power rule, the derivative [tex]f'(x)=-8x^{-2}=-\frac{8}{x^2}[/tex]. Substituting in -1 for x gives us a derivative of [tex]f'(-1)=-\frac{8}{(-1)^2} =-\frac{8}{1}=-8[/tex]
