Find the derivative of the following functions from first principle
.(i) `x^3-27`
(ii) `(x - 1) (x 2)`
(iii) `1/(x^2)`
(iv) `(x+1)/(x-1)`

Explanation

To find the derivatives of the given functions from first principles, we will use the definition of the derivative:

\[ f'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h} \]

Let's solve each part step by step.

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