(C)
(D)
17.If f(x) = ln(cos(3x)), then f′(x) =
(A)3 sec(3x)
(B)3 tan(3x)
(C)−3 tan(3x)
(D)−3 cot(3x)
18.If f(x) = dt, then f′(−4) =
17.If f(x) = ln(cos(3x)), then f′(x) =
(A)3 sec(3x)
(B)3 tan(3x)
(C)−3 tan(3x)
(D)−3 cot(3x)
18.If f(x) = dt, then f′(−4) =