SOLUTION: I'm stuck on the question, Find all values of x in the interval [0, 2𝜋] that satisfy the equation. (Enter your answers as a comma-separated list.) 27cot^2(x)=9 Any help wo

Algebra ->  Trigonometry-basics -> SOLUTION: I'm stuck on the question, Find all values of x in the interval [0, 2𝜋] that satisfy the equation. (Enter your answers as a comma-separated list.) 27cot^2(x)=9 Any help wo      Log On


   



Question 1195189: I'm stuck on the question,
Find all values of x in the interval [0, 2𝜋] that satisfy the equation. (Enter your answers as a comma-separated list.)
27cot^2(x)=9
Any help would be appreciated, especially a step by step tutorial on how it's done

Answer by ikleyn(52906) About Me  (Show Source):
You can put this solution on YOUR website!
.
I'm stuck on the question,
Find all values of x in the interval [0, 2𝜋] that satisfy the equation.
(Enter your answers as a comma-separated list.)
27cot^2(x)=9
Any help would be appreciated, especially a step by step tutorial on how it's done
~~~~~~~~~~~~~~~~~~~


            See my step-by-step solution below.


Your starting equation is

    27*cot^2(x) = 9


Divide both sides by 27. You will get

    cot^2(x) = 1%2F3


Take square root of both sides

    cot(x) = +/- sqrt%281%2F3%29 = +/- sqrt%283%29%2F3.    (1)


It implies that  x = pi%2F3,  2pi%2F3,  4pi%2F3,  5pi%2F3.    (2)



    If you ask me, how (2) follows from (1), the answer is 
    that they are the TABLE angles,

    which every student must know as he (or she) 
    knows the multiplication table.

    In other words, this knowledge is PRE-REQUISITE
    which a student must have starting to solve such problems.


ANSWER.  There are 4 values for x. They are pi%2F3,  2pi%2F3,  4pi%2F3,  5pi%2F3.

Solved and explained step by step.