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Find the sine and cosine values for an angle of $frac{5pi}{4}$ radians on the unit circle.

Answer 1

Abigail Nelson

Ava Martin

To find the sine and cosine values for an angle of $\frac{5\pi}{4}$ radians, we need to locate this angle on the unit circle.

First, we recognize that $\frac{5\pi}{4}$ radians is in the third quadrant because it is more than $\pi$ radians (180 degrees) but less than $\frac{3\pi}{2}$ radians (270 degrees).

The reference angle for $\frac{5\pi}{4}$ radians is $\frac{5\pi}{4} – \pi = \frac{\pi}{4}$ radians.

In the third quadrant, the sine and cosine values are both negative. For the reference angle $\frac{\pi}{4}$, the sine and cosine values are both $\frac{\sqrt{2}}{2}$.

Therefore, the sine and cosine values for $\frac{5\pi}{4}$ radians are:

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

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

Answer 2

Alex Thompson

Joseph Robinson

To determine the sine and cosine values for $frac{5pi}{4}$ radians, we use the unit circle.

$frac{5pi}{4}$ radians is located in the third quadrant because it is greater than $pi$ (180 degrees) but less than $2pi$ (360 degrees).

The reference angle for $frac{5pi}{4}$ is $frac{pi}{4}$.

For $frac{pi}{4}$, the sine and cosine values are both $frac{sqrt{2}}{2}$.

Since the angle is in the third quadrant, both sine and cosine values will be negative, giving:

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

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

Answer 3

Amelia Mitchell

Samuel Scott

To find the sine and cosine for $frac{5pi}{4}$ radians:

1. $frac{5pi}{4}$ is in the third quadrant.

2. Reference angle: $frac{pi}{4}$.

3. Values for $frac{pi}{4}$: $frac{sqrt{2}}{2}$.

4. In the third quadrant, both values are negative:

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

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