In Exercises 1-4, verify the identity. 1. cos(n + ) = (1)n cos , n is an integer 2. sin(n + ) = (1)n sin

In Exercises 1-4, verify the identity.
1. cos(nπ + Θ) = (−1)n cos Θ, n is an integer
2. sin(nπ + Θ) = (−1)n sin Θ, n is an integer
3. a sin BΘ + b cos BΘ = √a2 + b2 sin(BΘ + C), where C = arctan(b / a) and a > 0
4. a sin BΘ + b cos BΘ = √a2 + b2 cos(BΘ − C), where C = arctan(a / b) and b > 0