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Find the value of $x$ such that $cos(x) = -frac{1}{2}$ and $sin(x)$ is negative on the unit circle.

Answer 1

Abigail Nelson

Abigail Nelson

To solve for $x$ such that $\cos(x) = -\frac{1}{2}$ and $\sin(x)$ is negative on the unit circle, follow these steps:

1. Identify the angles where $\cos(x) = -\frac{1}{2}$. This occurs at $x = \frac{2\pi}{3}$ and $x = \frac{4\pi}{3}$ in radians.

2. Determine which of these angles has a negative sine value. The sine function is negative in the third and fourth quadrants.

3. Since $\frac{2\pi}{3}$ is in the second quadrant and $\frac{4\pi}{3}$ is in the third quadrant, we choose $x = \frac{4\pi}{3}$.

Therefore, the value of $x$ is:

$ x = \frac{4\pi}{3} $

Answer 2

Alex Thompson

Ava Martin

To find $x$ where $cos(x) = -frac{1}{2}$ and $sin(x)$ is negative:

1. Note that $cos(x) = -frac{1}{2}$ at angles $x = frac{2pi}{3}$ and $x = frac{4pi}{3}$.

2. Check the sine value: $sin(x)$ is negative in the third and fourth quadrants.

3. Since $frac{4pi}{3}$ is in the third quadrant where $sin(x)$ is negative, the answer is:

$ x = frac{4pi}{3} $

Answer 3

Amelia Mitchell

Henry Green

Solve for $x$ where $cos(x) = -frac{1}{2}$ and $sin(x)$ is negative.

The angle $x = frac{4pi}{3}$ satisfies both conditions.

$ x = frac{4pi}{3} $