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Find the values of $cos( heta)$ and $sin( heta)$ for $ heta = frac{5pi}{4}$

Answer 1

Abigail Nelson

John Anderson

To find the values of $\cos(\theta)$ and $\sin(\theta)$ for $\theta = \frac{5\pi}{4}$, we start by locating the angle on the unit circle. The angle $\frac{5\pi}{4}$ is in the third quadrant.

In the third quadrant, both sine and cosine values are negative. The reference angle for $\frac{5\pi}{4}$ is $\pi/4$, for which the cosine and sine values are both $\frac{\sqrt{2}}{2}$.

Therefore:

$\cos\left(\frac{5\pi}{4}\right) = -\frac{\sqrt{2}}{2}$

$\sin\left(\frac{5\pi}{4}\right) = -\frac{\sqrt{2}}{2}$

Answer 2

Alex Thompson

Abigail Nelson

To solve for $cos( heta)$ and $sin( heta)$ where $ heta = frac{5pi}{4}$, follow these steps:

1. Identify the quadrant. The angle $ heta = frac{5pi}{4}$ is in the third quadrant where both sine and cosine are negative.

2. Determine the reference angle, which is $pi/4$. The values for sine and cosine at $pi/4$ are $frac{sqrt{2}}{2}$.

3. Apply the signs based on the quadrant:

$cosleft(frac{5pi}{4}
ight) = -frac{sqrt{2}}{2}$

$sinleft(frac{5pi}{4}
ight) = -frac{sqrt{2}}{2}$

Answer 3

Amelia Mitchell

Ella Lewis

For $ heta = frac{5pi}{4}$:

The reference angle is $pi/4$.

In the third quadrant, both sine and cosine are negative.

Thus:

$cosleft(frac{5pi}{4}
ight) = -frac{sqrt{2}}{2}$

$sinleft(frac{5pi}{4}
ight) = -frac{sqrt{2}}{2}$