Question

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

Answer 1

Here is your equation:\[f(x) = \frac{ 8 }{ x }\] we can rewrite the "x" as this\[f(x) = 8x^{-1}\]then use your formula for derivatives:
\[\frac{ d }{ dx }x^{n} = nx^{n-1}\]after you have solved it's derivative, plug in -1 for your "x" and solve it.