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Calculate the sine and cosine values for $225^{circ}$ using the unit circle.

Answer 1

Abigail Nelson

Thomas Walker

The unit circle helps us determine the sine and cosine values for any given angle. For the angle $225^{\circ}$, we need to find its location on the unit circle.

The angle $225^{\circ}$ is in the third quadrant. In this quadrant, both sine and cosine values are negative. We can also express $225^{\circ}$ as $180^{\circ} + 45^{\circ}$, where $45^{\circ}$ is a reference angle.

From the unit circle, we know that the coordinates for $45^{\circ}$ are $(\frac{\sqrt{2}}{2}, \frac{\sqrt{2}}{2})$. Since $225^{\circ}$ is in the third quadrant, the sine and cosine values will be negative:

$\cos(225^{\circ}) = -\frac{\sqrt{2}}{2}$

$\sin(225^{\circ}) = -\frac{\sqrt{2}}{2}$

Thus, the sine and cosine values for $225^{\circ}$ are:

$\cos(225^{\circ}) = -\frac{\sqrt{2}}{2}$

$\sin(225^{\circ}) = -\frac{\sqrt{2}}{2}$

Answer 2

Alex Thompson

James Taylor

To find the sine and cosine values for $225^{circ}$ on the unit circle, we first note that $225^{circ}$ is located in the third quadrant. In this quadrant, the sine and cosine values are both negative.

The angle $225^{circ}$ can be represented as $180^{circ} + 45^{circ}$. The reference angle here is $45^{circ}$, whose coordinates on the unit circle are $(frac{sqrt{2}}{2}, frac{sqrt{2}}{2})$.

Since $225^{circ}$ is in the third quadrant, we take the negative of these coordinates:

$cos(225^{circ}) = -frac{sqrt{2}}{2}$

$sin(225^{circ}) = -frac{sqrt{2}}{2}$

Thus, the values for $225^{circ}$ are:

$cos(225^{circ}) = -frac{sqrt{2}}{2}$

$sin(225^{circ}) = -frac{sqrt{2}}{2}$

Answer 3

Amelia Mitchell

Olivia Lee

First, locate $225^{circ}$ on the unit circle. It is in the third quadrant, where both sine and cosine are negative.

The angle $225^{circ}$ can be written as $180^{circ} + 45^{circ}$. The reference angle $45^{circ}$ has coordinates $(frac{sqrt{2}}{2}, frac{sqrt{2}}{2})$.

Therefore,

$cos(225^{circ}) = -frac{sqrt{2}}{2}$

$sin(225^{circ}) = -frac{sqrt{2}}{2}$