1. **State the problem:** We need to find the derivative of the function $f(x) = 3x^2 - 7x + 1$ using the limit definition of the derivative:
$$f'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}$$
and then evaluate $f'(x)$ at $x=2$.
2. **Apply the limit definition:** Substitute $f(x+h)$ and $f(x)$:
$$f(x+h) = 3(x+h)^2 - 7(x+h) + 1$$
$$= 3(x^2 + 2xh + h^2) - 7x - 7h + 1$$
$$= 3x^2 + 6xh + 3h^2 - 7x - 7h + 1$$
3. **Calculate the difference quotient:**
$$\frac{f(x+h) - f(x)}{h} = \frac{(3x^2 + 6xh + 3h^2 - 7x - 7h + 1) - (3x^2 - 7x + 1)}{h}$$
Simplify the numerator:
$$= \frac{3x^2 + 6xh + 3h^2 - 7x - 7h + 1 - 3x^2 + 7x - 1}{h}$$
$$= \frac{6xh + 3h^2 - 7h}{h}$$
4. **Cancel common factor $h$:**
$$= \frac{\cancel{h}(6x + 3h - 7)}{\cancel{h}} = 6x + 3h - 7$$
5. **Take the limit as $h \to 0$:**
$$f'(x) = \lim_{h \to 0} (6x + 3h - 7) = 6x - 7$$
6. **Evaluate at $x=2$:**
$$f'(2) = 6(2) - 7 = 12 - 7 = 5$$
**Final answer:**
$$f'(x) = 6x - 7$$
$$f'(2) = 5$$
Derivative Limit Abf61D
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