Derivative At 2 B20A5C
1. **State the problem:** We want to find the derivative of the function $$f(x) = x^2 + 1$$ at the point $$x=2$$.
2. **Recall the definition of the derivative:** The derivative at a point $$x=a$$ is the limit of the average rate of change as $$x$$ approaches $$a$$:
$$
f'(a) = \lim_{x \to a} \frac{f(x) - f(a)}{x - a}
$$
This represents the instantaneous rate of change or the slope of the tangent line at $$x=a$$.
3. **Use the table values:** The table shows average rates of change for intervals approaching $$x=2$$ from both sides:
- At $$x=1.9$$, average rate is $$3.9$$
- At $$x=1.99$$, average rate is $$3.99$$
- At $$x=1.999$$, average rate is $$3.999$$
- At $$x=2.001$$, average rate is $$4.001$$
- At $$x=2.01$$, average rate is $$4.01$$
- At $$x=2.1$$, average rate is $$4.1$$
4. **Interpret the limit:** As $$x$$ gets closer to $$2$$, the average rate of change approaches $$4$$.
5. **Confirm by direct differentiation:** Using the power rule,
$$
f'(x) = 2x
$$
So at $$x=2$$,
$$
f'(2) = 2 \times 2 = 4
$$
**Final answer:** The derivative of $$f(x) = x^2 + 1$$ at $$x=2$$ appears to be $$4$$.