Answer:
For the domain and range, Period, and Two Vertical Asymptotes is stated below
Explanation:
For the function f(x) = - 2 cot 3x. 
lets state the following as follows,
y = -2[cos(3x)/sin(3x)] 
For the Domain 
All Real Numbers except with sin(3x)=0, 
All Real Numbers except x = 0 or pi/3
 For the Range=All Real Numbers 
For the given Period = (2pi/3) = (2/3)pi 
For Two Vertical Asymptotes:: x = 0 and x = pi/3