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Determine the exact values of sine and cosine for the angle $ frac{pi}{4} $ using the unit circle

Answer 1

Abigail Nelson

Matthew Carter

To find the exact values of sine and cosine for the angle $ \frac{\pi}{4} $, we use the unit circle.

For $ \theta = \frac{\pi}{4} $, the coordinates on the unit circle are:

$ ( \cos( \frac{\pi}{4} ), \sin( \frac{\pi}{4} )) $

Since $ \frac{\pi}{4} $ is an angle in the first quadrant where sine and cosine values are positive, we use the 45-degree reference angle values. We have:

$ \cos( \frac{\pi}{4}) = \frac{\sqrt{2}}{2} $

$ \sin( \frac{\pi}{4}) = \frac{\sqrt{2}}{2} $

Thus, the exact values are:

$ \cos( \frac{\pi}{4}) = \frac{\sqrt{2}}{2} $

$ \sin( \frac{\pi}{4}) = \frac{\sqrt{2}}{2} $

Answer 2

Alex Thompson

Alex Thompson

To find the exact values of sine and cosine for the angle $ frac{pi}{4} $, we use the unit circle.

For $ heta = frac{pi}{4} $, the coordinates on the unit circle are:

$ ( cos( frac{pi}{4} ), sin( frac{pi}{4} )) $

Since $ frac{pi}{4} $ is an angle in the first quadrant, we have:

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

$ sin( frac{pi}{4}) = frac{sqrt{2}}{2} $

Answer 3

Amelia Mitchell

Ella Lewis

To find the exact values of sine and cosine for the angle $ frac{pi}{4} $:

For $ heta = frac{pi}{4} $, we have:

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

$ sin( frac{pi}{4}) = frac{sqrt{2}}{2} $