1. **State the problem:** Solve the inequality $$\frac{3\cos(x)}{\sqrt{2} - 2\sin(x)} \geq 0$$ for $x$.
2. **Understand the inequality:** A fraction is non-negative if its numerator and denominator have the same sign (both positive or both negative) or if the numerator is zero.
3. **Analyze numerator:** $3\cos(x) \geq 0$ implies $\cos(x) \geq 0$.
4. **Analyze denominator:** $\sqrt{2} - 2\sin(x) \neq 0$ (denominator cannot be zero).
5. **Find when denominator is zero:**
$$\sqrt{2} - 2\sin(x) = 0 \implies 2\sin(x) = \sqrt{2} \implies \sin(x) = \frac{\sqrt{2}}{2}$$
This happens at $x = \frac{\pi}{4} + 2k\pi$ and $x = \frac{3\pi}{4} + 2k\pi$, $k \in \mathbb{Z}$.
6. **Determine sign of denominator:**
- For $\sin(x) < \frac{\sqrt{2}}{2}$, denominator $>0$.
- For $\sin(x) > \frac{\sqrt{2}}{2}$, denominator $<0$.
7. **Determine sign of numerator:**
$\cos(x) \geq 0$ means $x \in [-\frac{\pi}{2} + 2k\pi, \frac{\pi}{2} + 2k\pi]$.
8. **Combine conditions for fraction $\geq 0$:**
- Case 1: numerator $\geq 0$ and denominator $>0$.
- Case 2: numerator $\leq 0$ and denominator $<0$.
9. **Case 1:**
$$\cos(x) \geq 0 \quad \text{and} \quad \sin(x) < \frac{\sqrt{2}}{2}$$
10. **Case 2:**
$$\cos(x) \leq 0 \quad \text{and} \quad \sin(x) > \frac{\sqrt{2}}{2}$$
11. **Include points where numerator is zero:**
$$\cos(x) = 0 \implies x = \frac{\pi}{2} + k\pi$$
At these points, fraction equals zero (allowed).
12. **Final solution:**
$$\boxed{\left\{ x \mid (\cos(x) \geq 0 \text{ and } \sin(x) < \frac{\sqrt{2}}{2}) \text{ or } (\cos(x) \leq 0 \text{ and } \sin(x) > \frac{\sqrt{2}}{2}) \right\} \cup \left\{ x \mid \cos(x) = 0 \right\}}$$
This describes all $x$ where the original inequality holds, excluding points where denominator is zero.
Trig Inequality 8268Af
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