where is f(x)=12cos(3x) equal to zero. so far i have pi/2+n2pi.. i am not sure about pi/2
Since cos(θ)=0 when θ=%pi;/2+k%pi; where k∈ℤ, or k is any integer, the solution to:
Acos(3x)=0 where A=any non-zero number
would be
3x=π/2+kπ, or
x=π/6+kπ/3