1. **Problem Statement:** Find the maximum, minimum, relative maximum, and relative minimum values of the function $$f(x) = \sin(x^2)$$ over the interval $$(0, 4\pi)$$.
2. **Formula and Rules:** To find extrema, we first find critical points by solving $$f'(x) = 0$$ where $$f'(x)$$ is the derivative of $$f(x)$$.
3. **Derivative Calculation:** Using the chain rule,
$$f'(x) = \cos(x^2) \cdot 2x = 2x \cos(x^2)$$.
4. **Find Critical Points:** Set $$f'(x) = 0$$:
$$2x \cos(x^2) = 0$$
This implies either
$$x = 0$$ or $$\cos(x^2) = 0$$.
Since the interval is $$(0, 4\pi)$$, exclude $$x=0$$.
5. **Solve $$\cos(x^2) = 0$$:**
$$\cos(\theta) = 0$$ at $$\theta = \frac{\pi}{2} + k\pi$$ for integers $$k$$.
Set $$x^2 = \frac{\pi}{2} + k\pi$$.
6. **Find $$x$$ values:**
$$x = \sqrt{\frac{\pi}{2} + k\pi}$$ for integers $$k$$ such that $$0 < x < 4\pi$$.
7. **Determine $$k$$ range:**
Since $$x < 4\pi \approx 12.566$$,
$$x^2 < (4\pi)^2 = 16\pi^2 \approx 157.91$$.
So,
$$\frac{\pi}{2} + k\pi < 157.91$$
$$k < \frac{157.91 - \frac{\pi}{2}}{\pi} \approx \frac{157.91 - 1.57}{3.14} \approx 49.5$$.
So $$k = 0,1,2,...,49$$.
8. **Evaluate $$f(x)$$ at critical points:**
At each $$x_k = \sqrt{\frac{\pi}{2} + k\pi}$$,
$$f(x_k) = \sin(x_k^2) = \sin\left(\frac{\pi}{2} + k\pi\right)$$.
Since $$\sin\left(\frac{\pi}{2} + k\pi\right) = (-1)^k$$,
- For even $$k$$, $$f(x_k) = 1$$ (relative maxima).
- For odd $$k$$, $$f(x_k) = -1$$ (relative minima).
9. **Check endpoints:**
At $$x=0$$ (excluded), at $$x=4\pi$$,
$$f(4\pi) = \sin((4\pi)^2) = \sin(16\pi^2)$$.
Since $$16\pi^2$$ is not a multiple of $$\pi$$, approximate:
$$16\pi^2 \approx 157.91$$,
$$157.91 \mod 2\pi \approx 157.91 - 25 \times 2\pi = 157.91 - 157.08 = 0.83$$,
so $$f(4\pi) \approx \sin(0.83) \approx 0.74$$.
10. **Summary:**
- Relative maxima at $$x = \sqrt{\frac{\pi}{2} + 2m\pi}$$ with value 1.
- Relative minima at $$x = \sqrt{\frac{\pi}{2} + (2m+1)\pi}$$ with value -1.
- Absolute maximum value is 1.
- Absolute minimum value is -1.
**Final answer:**
- Maximum value: $$1$$
- Minimum value: $$-1$$
- Relative maxima at $$x = \sqrt{\frac{\pi}{2} + 2m\pi}$$ for integers $$m$$ with $$0 \leq m \leq 24$$.
- Relative minima at $$x = \sqrt{\frac{\pi}{2} + (2m+1)\pi}$$ for integers $$m$$ with $$0 \leq m \leq 24$$.
Sin X Squared Extrema 3C3193
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