Find all solutions of the equation in the interval [tex][0, 2\pi)[/tex].

[tex]
(2 \sin x - 1)(2 \cos x + 1) = 0
[/tex]

Write your answer in radians in terms of [tex]\pi[/tex]. If there is more than one solution, separate them with commas.

[tex]
x = \square
[/tex]



Answer :

To find all solutions to the equation [tex]\((2 \sin x - 1)(2 \cos x + 1) = 0\)[/tex] in the interval [tex]\([0, 2\pi)\)[/tex], we need to solve both factors separately:

1. [tex]\(2 \sin x - 1 = 0\)[/tex]
2. [tex]\(2 \cos x + 1 = 0\)[/tex]

### Solving [tex]\(2 \sin x - 1 = 0\)[/tex]

1. Set [tex]\(2 \sin x - 1 = 0\)[/tex].
2. Solving for [tex]\(\sin x\)[/tex], we get:
[tex]\[ \sin x = \frac{1}{2} \][/tex]
3. The general solutions for [tex]\(\sin x = \frac{1}{2}\)[/tex] are:
[tex]\[ x = \frac{\pi}{6} + 2k\pi \quad \text{and} \quad x = \pi - \frac{\pi}{6} + 2k\pi \][/tex]
where [tex]\(k\)[/tex] is an integer.

4. In the interval [tex]\([0, 2\pi)\)[/tex], we find:
[tex]\[ x = \frac{\pi}{6} \quad \text{and} \quad x = \frac{5\pi}{6} \][/tex]

### Solving [tex]\(2 \cos x + 1 = 0\)[/tex]

1. Set [tex]\(2 \cos x + 1 = 0\)[/tex].
2. Solving for [tex]\(\cos x\)[/tex], we get:
[tex]\[ \cos x = -\frac{1}{2} \][/tex]
3. The general solutions for [tex]\(\cos x = -\frac{1}{2}\)[/tex] are:
[tex]\[ x = \frac{2\pi}{3} + 2k\pi \quad \text{and} \quad x = \frac{4\pi}{3} + 2k\pi \][/tex]
where [tex]\(k\)[/tex] is an integer.

4. In the interval [tex]\([0, 2\pi)\)[/tex], we find:
[tex]\[ x = \frac{2\pi}{3} \quad \text{and} \quad x = \frac{4\pi}{3} \][/tex]

### Combining Solutions

Thus, the solutions of the equation [tex]\((2 \sin x - 1)(2 \cos x + 1) = 0\)[/tex] in the interval [tex]\([0, 2\pi)\)[/tex] are:
[tex]\[ x = \frac{\pi}{6}, \frac{5\pi}{6}, \frac{2\pi}{3}, \frac{4\pi}{3} \][/tex]

### Final Answer

[tex]\[ x = \frac{\pi}{6}, \frac{5\pi}{6}, \frac{2\pi}{3}, \frac{4\pi}{3} \][/tex]

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