At least one of the answers above is NOT correct. 2 of the questions remain unanswered. (1 point) (a) Using a trig identity, write x(t) = -2 cos(6t) +2 sin(6t) using only one cosine function. x(t): = sqrt(8)(cos(6t+1)) help (formulas) (b) Using a trig identity, write x(t) = 2 cos(6t) + 2 sin(6t) using only one cosine function. x(t) = help (formulas) (c) Using a trig identity, write x(t) = e−2 (-2 cos(6t) + 2 sin(6t)) using only one cosine function in your answer. x(t)= = Hint: help (formulas)