1. **State the problem:** We need to determine whether the turning points at $(-5, 275)$ and $(2, -68)$ on the curve $y = 2x^3 + 9x^2 - 60x$ are maxima or minima.
2. **Recall the formula:** Turning points occur where the first derivative $y'$ is zero. To classify them, we use the second derivative test:
- If $y''(x) > 0$, the turning point is a local minimum.
- If $y''(x) < 0$, the turning point is a local maximum.
3. **Find the first derivative:**
$$y = 2x^3 + 9x^2 - 60x$$
$$y' = \frac{d}{dx}(2x^3) + \frac{d}{dx}(9x^2) - \frac{d}{dx}(60x) = 6x^2 + 18x - 60$$
4. **Find the second derivative:**
$$y'' = \frac{d}{dx}(6x^2 + 18x - 60) = 12x + 18$$
5. **Evaluate the second derivative at each turning point:**
- At $x = -5$:
$$y''(-5) = 12(-5) + 18 = -60 + 18 = -42$$
Since $y''(-5) < 0$, the turning point at $(-5, 275)$ is a local maximum.
- At $x = 2$:
$$y''(2) = 12(2) + 18 = 24 + 18 = 42$$
Since $y''(2) > 0$, the turning point at $(2, -68)$ is a local minimum.
**Final answer:**
- Turning point $(-5, 275)$ is a local maximum.
- Turning point $(2, -68)$ is a local minimum.
Turning Points 20249F
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