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Find the sine and cosine of $45^{circ}$ using the unit circle.

Answer 1

Abigail Nelson

Ava Martin

To find the sine and cosine of $45^{\circ}$ using the unit circle, we need to locate $45^{\circ}$ on the unit circle chart.

The coordinates of the point where the $45^{\circ}$ angle intersects the unit circle are $(\frac{\sqrt{2}}{2}, \frac{\sqrt{2}}{2})$.

Thus, the sine of $45^{\circ}$ is the y-coordinate:

$\sin(45^{\circ}) = \frac{\sqrt{2}}{2}$

And the cosine of $45^{\circ}$ is the x-coordinate:

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

Answer 2

Alex Thompson

Chloe Evans

First, we identify the $45^{circ}$ angle on the unit circle. The unit circle has the property that any angle’s coordinates are $(cos( heta), sin( heta))$.

For $45^{circ}$, we find that the coordinates are $(frac{sqrt{2}}{2}, frac{sqrt{2}}{2})$.

Therefore,

$sin(45^{circ}) = frac{sqrt{2}}{2}$

and

$cos(45^{circ}) = frac{sqrt{2}}{2}$

Answer 3

Amelia Mitchell

Charlotte Davis

For $45^{circ}$ on the unit circle, the coordinates are $(frac{sqrt{2}}{2}, frac{sqrt{2}}{2})$.

So,

$sin(45^{circ}) = frac{sqrt{2}}{2}$

$cos(45^{circ}) = frac{sqrt{2}}{2}$