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I need help in math can you please help me please

I need help in math can you please help me please-example-1
User Max Malyk
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1 Answer

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Trigonometric Equations

Solve:


9\tan ^3x=3\tan x

In the interval [0,2pi)

We have to find all the values of x that make equality stand. First, divide by 3:


3\tan ^3x=\tan x

Subtract tan x


3\tan ^3x-\tan x=0

Factor tan x out:


\tan x(3\tan ^2x-1)=0

One solution comes immediately:

tan x = 0

There are two angles whose tangent is 0:


x=0\text{ , x=}\pi

The other solutions come when equating:


3\tan ^2x-1=0

Adding 1, and dividing by 3:


\tan ^2x=(1)/(3)

Taking the square root:


\tan x=\sqrt[\square]{(1)/(3)}=\pm\frac{\sqrt[]{3}}{3}

The positive answer gives us two solutions:


\tan x=\frac{\sqrt[]{3}}{3}

x=pi/6 and x=7pi/6

The negative answer also gives us two solutions:


\tan x=-\frac{\sqrt[]{3}}{3}

x=5pi/6, 11pi/6

Summarizing the solutions are:

{

User PanxShaz
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