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$ ext{Find the value of cosine for an angle on the unit circle}$

Answer 1

Abigail Nelson

Mia Harris

Let’s find the value of $\cos(\frac{\pi}{4})$ on the unit circle.

The angle $\frac{\pi}{4}$ is equivalent to 45 degrees.

On the unit circle, the coordinates of the point at an angle of $\frac{\pi}{4}$ are $(\frac{\sqrt{2}}{2}, \frac{\sqrt{2}}{2})$.

Thus, the cosine of $\frac{\pi}{4}$ is $\cos(\frac{\pi}{4}) = \frac{\sqrt{2}}{2}$.

Answer 2

Alex Thompson

Samuel Scott

Determine the value of $cos(frac{2pi}{3})$ on the unit circle.

The angle $frac{2pi}{3}$ is equivalent to 120 degrees.

On the unit circle, the coordinates of the point at an angle of $frac{2pi}{3}$ are $(-frac{1}{2}, frac{sqrt{3}}{2})$.

Therefore, the cosine of $frac{2pi}{3}$ is $cos(frac{2pi}{3}) = -frac{1}{2}$.

Answer 3

Amelia Mitchell

Abigail Nelson

What is the value of $cos(pi)$ on the unit circle?

At an angle of $pi$, which is 180 degrees, the coordinates on the unit circle are $(-1, 0)$.

Therefore, the cosine of $pi$ is $cos(pi) = -1$.