(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

g(x) = 4x - tanx

2. Relevant equations

3. The attempt at a solution

[tex]g(\theta) = 4\theta - tan\theta[/tex]

[tex]g'(\theta)=4-sec^{2}\theta[/tex]

[tex]g'(\theta)=\frac{4cos^{2}\theta-1}{cos^{2}\theta}[/tex]

[tex]g'(\theta)=\frac{-4sin^{2}\theta}{cos^{2}\theta}[/tex]

[tex]-4tan^{2}\theta=0[/tex]

[tex]-4(tan\theta)(tan\theta)=0[/tex]

[tex]\theta = arctan0[/tex]

[tex]\theta = k\pi[/tex]

So, that lists the zeros of the derivative if I am correct. I believe the other critical points are pi/2 + kpi, where tan is undefined. That is all of the critical points correct?

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# Homework Help: Critical Points

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