Question

Find the derivative of f(x) = 8 divided by x at x = -1.

Answer 1

-8

Explanation:

We can write
`f(x)=(8)/(x)`, or equivalently
`f(x)=8x^(-1)`. Using the power rule, the derivative
`f'(x)=-8x^(-2)=-(8)/(x^2)`. Substituting in -1 for x gives us a derivative of
`f'(-1)=-(8)/((-1)^2) =-(8)/(1)=-8`