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$ ext{Find the sine and cosine of a 45-degree angle}$

Answer 1

Abigail Nelson

Alex Thompson

To find the sine and cosine of a 45-degree angle, we can use the unit circle. A 45-degree angle corresponds to $\frac{\pi}{4}$ radians.

On the unit circle, the coordinates for $\frac{\pi}{4}$ are given by $\left( \cos \frac{\pi}{4}, \sin \frac{\pi}{4} \right)$.

We know from trigonometric identities that:

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

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

Therefore, the sine and cosine of a 45-degree angle are both $\frac{\sqrt{2}}{2}$.

Answer 2

Alex Thompson

Benjamin Clark

To determine the sine and cosine values for a 45-degree angle, we can refer to the unit circle. A 45-degree angle is the same as $frac{pi}{4}$ radians.

The unit circle shows that the coordinates for $frac{pi}{4}$ are $left( cos frac{pi}{4}, sin frac{pi}{4}
ight)$.

From trigonometric properties:

$cos frac{pi}{4} = frac{1}{sqrt{2}} = frac{sqrt{2}}{2}$

$sin frac{pi}{4} = frac{1}{sqrt{2}} = frac{sqrt{2}}{2}$

Thus, both sine and cosine of 45 degrees equal $frac{sqrt{2}}{2}$.

Answer 3

Amelia Mitchell

Isabella Walker

For a 45-degree angle, which is $frac{pi}{4}$ radians:

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

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

Hence, $cos 45^circ$ and $sin 45^circ$ are both $frac{sqrt{2}}{2}$.