# Maths

Find the derivative of y=1/x at x=1/4 Answer: 1/1/16

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1. y = 1/x
y' = -1/x^2
y'(1/4) = -1/(1/16) = -16

I think you lost a minus sign. And, of course, you have displayed the usual sloppiness with parentheses.

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posted by Steve

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