1. **Problem statement:** Given the graph of the derivative $y = f'(x)$ of a quartic function $y = f(x)$, analyze the following statements:
a) $f(x)$ is decreasing on $(-\infty, -2)$.
b) $f(x)$ has three critical points.
c) The minimum value of $f(x)$ on $[-2, 2]$ is $f(0)$.
d) Given $f(0) > 0$, the equation $f(x) = 0$ has at most 3 distinct solutions.
2. **Recall:**
- $f'(x) < 0$ means $f(x)$ is decreasing.
- Critical points of $f(x)$ occur where $f'(x) = 0$.
- Local extrema of $f(x)$ correspond to zeros of $f'(x)$ where the sign of $f'(x)$ changes.
- The number of roots of $f(x)$ relates to the behavior of $f'(x)$ and values of $f(x)$.
3. **Analyze (a):**
- On $(-\infty, -2)$, the graph of $f'(x)$ is below the $x$-axis (negative).
- Therefore, $f'(x) < 0$ on $(-\infty, -2)$.
- Hence, $f(x)$ is decreasing on $(-\infty, -2)$.
4. **Analyze (b):**
- The graph of $f'(x)$ crosses the $x$-axis at $x = -2, 0, 2$.
- These are the critical points of $f(x)$.
- There are exactly 3 critical points.
5. **Analyze (c):**
- On $[-2, 2]$, $f'(x)$ changes sign at $x = -2, 0, 2$.
- $f'(x)$ is positive on $(-2, 0)$ and negative on $(0, 2)$, so $f(x)$ increases then decreases.
- Thus, $f(0)$ is a local maximum, not minimum.
- Check endpoints: $f(-2)$ and $f(2)$ could be smaller.
- So the minimum on $[-2, 2]$ is not necessarily $f(0)$.
6. **Analyze (d):**
- Since $f(0) > 0$ and $f(x)$ is continuous,
- $f(x)$ has 3 critical points, so $f'(x)$ has 3 zeros.
- The quartic $f(x)$ can have up to 4 real roots.
- But with $f(0) > 0$ and shape of $f'(x)$, $f(x)$ crosses zero at most 3 times.
**Final answers:**
- (a) True
- (b) True
- (c) False
- (d) True
Derivative Graph Analysis E81F54
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