Solve and show work: if f(x)= -1/x^3 + 2/x^2 - 1/x, then f'(-1) =

f(x) = -x^-3 + 2x^-2 - x^-1

It's easier if you just write them as negative exponents instead of doing fractions.

f'(x) = 3x^-4 - 4x^-3 + x^-2
f'(-1) = 3(-1)^(-4) - 4(-1)^(-3) + (-1)^(-2)
= 3(1) - 4(-1) + 1
= 3 - 4 + 1
= 0

oops, 3 - (-4) + 1 = 8, not 0, my bad

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