Find the Exact Value by Using a Half-Angle Identity $\cos \frac { 5 \pi } { 12 }$

question 450

Multiple Choice

Find the exact value by using a half-angle identity.
- $\cos \frac { 5 \pi } { 12 }$

• A) \(\frac { 1 } { 2 } \sqrt { 2 + \sqrt { 3 } }\)
• B) \(\frac { 1 } { 2 } \sqrt { 2 - \sqrt { 3 } }\)
• C) \(- \frac { 1 } { 2 } \sqrt { 2 - \sqrt { 3 } }\)
• D) \(- \frac { 1 } { 2 } \sqrt { 2 + \sqrt { 3 } }\)

---

Definitions:

High-Maintenance

Refers to things or people requiring a lot of time, attention, or money.

Very Labor-Intensive

Involving or requiring strenuous effort; physically demanding.

Nonrenewable Sources

energy sources that cannot be replenished in a short period, like fossil fuels.

Renewable Sources

Energy sources that are replenished naturally, such as solar, wind, water, and geothermal energy.