Answer: Find the exact value of each expression. (Do not use a calculator.) See Example
Chapter 5, Problem 18(choose chapter or problem)
Find the exact value of each expression. (Do not use a calculator.) See Example 1. cos 7p9 cos 2p9 - sin7p9 sin2p9
Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
Becoming a subscriber
Or look for another answer