Question

Find the cosine of the following angles.(4 points)
cos
𝜋
6
cos
π
6
cos 90° cos 90°
cos
7𝜋
4 cos
7π
4
cos 240°cos 240°
√2
2
√ 2
2
−
1
2 −
1
2
00
√3
2
√ 3
2

Answer 1

Let's find the cosine values for the given angles:

1. **cos(π/6)**:
\[
\cos\left(\frac{\pi}{6}\right) = \frac{\sqrt{3}}{2}
\]

2. **cos(90°)**:
\[
\cos(90^\circ) = 0
\]

3. **cos(7π/4)**:
\[
\cos\left(\frac{7\pi}{4}\right) = \cos(315^\circ) = \frac{\sqrt{2}}{2}
\]

4. **cos(240°)**:
\[
\cos(240^\circ) = -\frac{1}{2}
\]

Now, let's summarize the answers:
- \( \cos\left(\frac{\pi}{6}\right) = \frac{\sqrt{3}}{2} \)
- \( \cos(90^\circ) = 0 \)
- \( \cos\left(\frac{7\pi}{4}\right) = \frac{\sqrt{2}}{2} \)
- \( \cos(240^\circ) = -\frac{1}{2} \)

If you need further information or details on any of these calculations, let me know!