Solving a Cosine Equation

Question

What are all solutions for $$	heta$$ to the equation $$2\cos(	heta)=1$$ on the interval $$[0, 2\pi]$$?

| $$	heta$$ (radians) | $$\cos(	heta)$$ |
|----------------------|----------------|
| 0                    | 1              |
| $$\frac{\pi}{3}$$       | $$\frac{1}{2}$$    |
| $$\frac{\pi}{2}$$       | 0              |
| $$\pi$$                  | -1             |
| $$\frac{5\pi}{3}$$       | $$\frac{1}{2}$$    |
| $$2\pi$$                | 1              |

Accepted Answer

$$	heta = \frac{\pi}{3} 	ext{ or } \frac{5\pi}{3}$$

Answer

$$	heta = \frac{\pi}{3} 	ext{ or } \frac{2\pi}{3}$$

Answer

$$	heta = \frac{\pi}{4} 	ext{ or } \frac{3\pi}{4}$$

Answer

$$	heta = \frac{\pi}{6} 	ext{ or } \frac{5\pi}{6}$$

Rank	User	Correct Count	Attempt Count	Total Time	Score
#1	chunxiangxu.cxu	1	1	0m 09s	91
#2	mihikadarbha	1	1	0m 51s	49
#3	danurizayo	1	1	39m 35s	-2,275

$\theta$ (radians)	$\cos(\theta)$
0	1
$\frac{\pi}{3}$	$\frac{1}{2}$
$\frac{\pi}{2}$	0
$\pi$	-1
$\frac{5\pi}{3}$	$\frac{1}{2}$
$2\pi$	1

Solving a Cosine Equation

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