For \small{f(x) = \frac{15}{ x}} , find \large{\frac{dy}{dx}} using the definition,
\small{\frac{dy}{dx} =
\displaystyle\lim_{\Delta x \to 0} \frac{\Delta y}{\Delta x} =
\displaystyle\lim_{\Delta x \to 0} \frac{f(x + \Delta x) - f(x)}{\Delta x}.}

(a) First, evaluate

(b) Using the

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