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

cos(x)+2tg(x) = 7/(4*cosx(x)) Solve for x on the real numbers set.

2. Relevant equations

tg(x) = sin(x)/cos(x) ,

cos^2(x) = 1-2*sin^2(x) ,

The determinant is D = b^2 - 4ac ,

Also cos(x) ,tg(x), sin(x) | -1 < x < 1

3. The attempt at a solution

For final arrangement I got is:

-8sin^2(x) + 8sin(x) - 3 = 0

But the determinant is 8^2 - 4*(-8)*(-3) which is 64 - 96 thus the equation doesn't have a real solution.

I checked on WolframAlpha and it has some weird solutions and I was also told that it does have a real solution.

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# Homework Help: Trigonometric Equation

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