a) Using a trig identity, write 3cos(4t) + 5sin(4t) using only one cosine function.
b) Using a trig identity, write z - 3cos(4t) + 5sin(4t) using only one cosine function.
c) Using a trig identity, write e^(-3cos(4t) + 5sin(4t)) using only one cosine function in your answer.