Tangent Equations 2Ba808
1. **Problem Statement:** Find the equation of the tangent line to the curve at the given $x$ value.
2. **Formula and Rules:** The equation of the tangent line at $x=a$ is given by:
$$y = f(a) + f'(a)(x - a)$$
where $f'(a)$ is the derivative of the function evaluated at $x=a$.
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### a) For $y = 2x^2 + x - 2$ at $x=0$:
3. Find the derivative:
$$f'(x) = \frac{d}{dx}(2x^2 + x - 2) = 4x + 1$$
4. Evaluate the function and derivative at $x=0$:
$$f(0) = 2(0)^2 + 0 - 2 = -2$$
$$f'(0) = 4(0) + 1 = 1$$
5. Write the tangent line equation:
$$y = f(0) + f'(0)(x - 0) = -2 + 1 \cdot x = x - 2$$
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### b) For $y = \sqrt{x} + 2$ at $x=1$:
6. Rewrite the function for differentiation:
$$y = x^{1/2} + 2$$
7. Find the derivative:
$$f'(x) = \frac{d}{dx}(x^{1/2} + 2) = \frac{1}{2}x^{-1/2} = \frac{1}{2\sqrt{x}}$$
8. Evaluate the function and derivative at $x=1$:
$$f(1) = \sqrt{1} + 2 = 1 + 2 = 3$$
$$f'(1) = \frac{1}{2\sqrt{1}} = \frac{1}{2}$$
9. Write the tangent line equation:
$$y = f(1) + f'(1)(x - 1) = 3 + \frac{1}{2}(x - 1) = \frac{1}{2}x + \frac{5}{2}$$
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**Final answers:**
- a) $y = x - 2$
- b) $y = \frac{1}{2}x + \frac{5}{2}$