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Find the value of $cos(-pi / 3)$ using the unit circle.

Answer 1

Abigail Nelson

Henry Green

To find $\cos(-\pi / 3)$, we can start by recognizing that the cosine function is even. This means $\cos(-x) = \cos(x)$. Therefore:

$\cos(-\pi / 3) = \cos(\pi / 3)$

From the unit circle, we know that:

$\cos(\pi / 3) = \frac{1}{2}$

So, the value of $\cos(-\pi / 3)$ is:

$\cos(-\pi / 3) = \frac{1}{2}$

Answer 2

Alex Thompson

Emily Hall

We start by using the property of the cosine function being even, which tells us:

$cos(-pi / 3) = cos(pi / 3)$

Next, we look at the unit circle to find the value of $cos(pi / 3)$. On the unit circle, $pi / 3$ radians corresponds to 60 degrees, and the x-coordinate (cosine) at this angle is:

$cos(pi / 3) = frac{1}{2}$

Therefore, the value of $cos(-pi / 3)$ is:

$cos(-pi / 3) = frac{1}{2}$

Answer 3

Amelia Mitchell

Michael Moore

Since $cos(-x) = cos(x)$, we have:

$cos(-pi / 3) = cos(pi / 3)$

Using the unit circle, we find:

$cos(pi / 3) = frac{1}{2}$

Thus:

$cos(-pi / 3) = frac{1}{2}$