1. **State the problem:** Solve the inequality $$\sin^2 x - \sin x \geq 0$$.
2. **Rewrite the inequality:** Factor the left side as a quadratic in terms of $\sin x$:
$$\sin^2 x - \sin x = \sin x (\sin x - 1) \geq 0$$.
3. **Analyze the product:** The product $\sin x (\sin x - 1)$ is greater than or equal to zero when both factors are non-negative or both are non-positive.
4. **Case 1: Both factors non-negative:**
$$\sin x \geq 0 \quad \text{and} \quad \sin x - 1 \geq 0 \implies \sin x \geq 1$$
Since $\sin x \leq 1$ always, this means:
$$\sin x = 1$$
which occurs at
$$x = \frac{\pi}{2} + 2k\pi, \quad k \in \mathbb{Z}$$.
5. **Case 2: Both factors non-positive:**
$$\sin x \leq 0 \quad \text{and} \quad \sin x - 1 \leq 0$$
The second inequality is always true since $\sin x - 1 \leq 0$ for all $x$.
So this reduces to:
$$\sin x \leq 0$$
which means $x$ is in intervals where sine is negative or zero:
$$x \in [\pi + 2k\pi, 2\pi + 2k\pi], \quad k \in \mathbb{Z}$$.
6. **Combine solutions:**
The solution set is:
$$\{x \mid \sin x = 1\} \cup \{x \mid \sin x \leq 0\}$$
which is:
$$x = \frac{\pi}{2} + 2k\pi \quad \text{or} \quad x \in [\pi + 2k\pi, 2\pi + 2k\pi], \quad k \in \mathbb{Z}$$.
**Final answer:**
$$\boxed{x = \frac{\pi}{2} + 2k\pi \quad \text{or} \quad x \in [\pi + 2k\pi, 2\pi + 2k\pi], \quad k \in \mathbb{Z}}$$
Sin Inequality 5577Da
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