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Solve the equation by factoring. (Enter your answers as a comma-separated list. Let k be any integer. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.)

2 cos(θ) tan(θ) − tan(θ) = 1 − 2 cos(θ)
θ = ?

Respuesta :

Answer:

[tex]\displaystyle \theta=\frac{\pi}{3}+2k\pi,\ \frac{5\pi}{3}+2k\pi,\ \frac{3\pi}{4}+2k\pi,\ \frac{7\pi}{4}+2k\pi[/tex]

Step-by-step explanation:

Trigonometric Equation

A trigonometric equation is any equation that contains one or more trigonometric functions. The solution of a trigonometric equation comes in the form of angles in radians or degrees.

Let's solve the equation

[tex]2cos\theta tan\theta - tan\theta=1-2cos\theta[/tex]

Factoring the left side of the equation by tan[tex]\theta[/tex]

[tex](2cos\theta - 1)tan\theta =1-2cos\theta[/tex]

Rearranging

[tex](2cos\theta - 1)tan\theta +2cos\theta-1=0[/tex]

Factoring again

[tex](2cos\theta - 1)(tan\theta +1)=0[/tex]

We get two separate equations to solve

[tex]\text{[1]\ \ \ }2cos\theta - 1=0[/tex]

[tex]\text{[2]\ \ \ }tan\theta +1=0[/tex]

Solving the first equation

[tex]\displaystyle cos\theta=\frac{1}{2}[/tex]

We get two solutions in the first rotation of [tex]\theta[/tex]

[tex]\displaystyle \theta=\frac{\pi}{3}[/tex]

[tex]\displaystyle \theta=\frac{5\pi}{3}[/tex]

The general solution, being k any integer:

[tex]\displaystyle \theta=\frac{\pi}{3}+2k\pi\\\displaystyle \theta=\frac{5\pi}{3}+2k\pi[/tex]

Solving the second equation

[tex]tan\theta=-1[/tex]

We also get two solutions in the first rotation of [tex]\theta[/tex]

[tex]\displaystyle \theta=\frac{3\pi}{4}[/tex]

[tex]\displaystyle \theta=\frac{7\pi}{4}[/tex]

The general solution, being k any integer:

[tex]\displaystyle \theta=\frac{3\pi}{4}+2k\pi\\\displaystyle \theta=\frac{7\pi}{4}+2k\pi[/tex]

The total solution is

[tex]\displaystyle \theta=\frac{\pi}{3}+2k\pi,\ \frac{5\pi}{3}+2k\pi,\ \frac{3\pi}{4}+2k\pi,\ \frac{7\pi}{4}+2k\pi[/tex]