1. **State the problem:** We want to find the derivative of the function $$f(x) = \frac{2}{x}$$ using the definition of the derivative, which is
$$f'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}.$$
2. **Write the difference quotient:** Substitute the function into the definition:
$$f'(x) = \lim_{h \to 0} \frac{\frac{2}{x+h} - \frac{2}{x}}{h}.$$
3. **Find a common denominator inside the numerator:**
$$\frac{2}{x+h} - \frac{2}{x} = \frac{2x - 2(x+h)}{x(x+h)} = \frac{2x - 2x - 2h}{x(x+h)} = \frac{-2h}{x(x+h)}.$$
4. **Substitute back into the difference quotient:**
$$f'(x) = \lim_{h \to 0} \frac{\frac{-2h}{x(x+h)}}{h} = \lim_{h \to 0} \frac{-2h}{x(x+h)} \cdot \frac{1}{h}.$$
5. **Cancel the common factor $h$:**
$$f'(x) = \lim_{h \to 0} \frac{-2\cancel{h}}{x(x+h)} \cdot \frac{1}{\cancel{h}} = \lim_{h \to 0} \frac{-2}{x(x+h)}.$$
6. **Evaluate the limit as $h \to 0$:**
$$f'(x) = \frac{-2}{x \cdot x} = \frac{-2}{x^2}.$$
7. **Conclusion:** The derivative of $$f(x) = \frac{2}{x}$$ is
$$f'(x) = -\frac{2}{x^2}.$$
**Answer:** $$f'(x) = -\frac{2}{x^2}.$$
Derivative Definition Cdeaaf
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