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What is the cosine of the angle $45^circ$ on the unit circle?

Answer 1

Abigail Nelson

Chloe Evans

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

On the unit circle, the coordinates for an angle of $45^\circ$ or $\frac{\pi}{4}$ radians are $(\frac{\sqrt{2}}{2}, \frac{\sqrt{2}}{2})$.

Thus, the cosine of $45^\circ$ is $\frac{\sqrt{2}}{2}$.

$ \cos 45^\circ = \frac{\sqrt{2}}{2} $

Answer 2

Alex Thompson

Michael Moore

First, convert 45 degrees to radians: $45^circ = frac{pi}{4}$ radians.

Recall that on the unit circle, the x-coordinate of a point gives the cosine of the angle.

For $frac{pi}{4}$ radians, the coordinates are $(frac{sqrt{2}}{2}, frac{sqrt{2}}{2})$.

Therefore, the cosine of $frac{pi}{4}$ is $frac{sqrt{2}}{2}$.

$ cos frac{pi}{4} = frac{sqrt{2}}{2} $

Answer 3

Amelia Mitchell

Christopher Garcia

The angle $45^circ$ equals $frac{pi}{4}$ radians.

On the unit circle, the cosine of $frac{pi}{4}$ is $frac{sqrt{2}}{2}$.

$ cos frac{pi}{4} = frac{sqrt{2}}{2} $