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sin(6*x)+cos(6*x)*sqrt(3)=-2*cos(8*x)

sin(6*x)+cos(6*x)*sqrt(3)=-2*cos(8*x) equation

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Numerical solution:

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The solution

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sin(6*x) + cos(6*x)*\/ 3  = -2*cos(8*x)
$$\sin{\left(6 x \right)} + \sqrt{3} \cos{\left(6 x \right)} = - 2 \cos{\left(8 x \right)}$$
Detail solution
Given the equation:
$$\sin{\left(6 x \right)} + \sqrt{3} \cos{\left(6 x \right)} = - 2 \cos{\left(8 x \right)}$$
Transform
$$\sin{\left(6 x \right)} + \sqrt{3} \cos{\left(6 x \right)} + 2 \cos{\left(8 x \right)} = 0$$
$$4 \sin{\left(7 x + \frac{5 \pi}{12} \right)} \cos{\left(x + \frac{\pi}{12} \right)} = 0$$
Consider each factor separately

Step


$$\cos{\left(x + \frac{\pi}{12} \right)} = 0$$
- this is the simplest trigonometric equation
We get:
$$\cos{\left(x + \frac{\pi}{12} \right)} = 0$$
This equation is transformed to
$$x + \frac{\pi}{12} = 2 \pi n + \operatorname{acos}{\left(0 \right)}$$
$$x + \frac{\pi}{12} = 2 \pi n - \pi + \operatorname{acos}{\left(0 \right)}$$
Or
$$x + \frac{\pi}{12} = 2 \pi n + \frac{\pi}{2}$$
$$x + \frac{\pi}{12} = 2 \pi n - \frac{\pi}{2}$$
, where n - is a integer
Move
$$\frac{\pi}{12}$$
to right part of the equation with the opposite sign, in total:
$$x = 2 \pi n + \frac{5 \pi}{12}$$
$$x = 2 \pi n - \frac{7 \pi}{12}$$

Step


$$\sin{\left(7 x + \frac{5 \pi}{12} \right)} = 0$$
- this is the simplest trigonometric equation
We get:
$$\sin{\left(7 x + \frac{5 \pi}{12} \right)} = 0$$
This equation is transformed to
$$7 x + \frac{5 \pi}{12} = 2 \pi n + \operatorname{asin}{\left(0 \right)}$$
$$7 x + \frac{5 \pi}{12} = 2 \pi n - \operatorname{asin}{\left(0 \right)} + \pi$$
Or
$$7 x + \frac{5 \pi}{12} = 2 \pi n$$
$$7 x + \frac{5 \pi}{12} = 2 \pi n + \pi$$
, where n - is a integer
Move
$$\frac{5 \pi}{12}$$
to right part of the equation with the opposite sign, in total:
$$7 x = 2 \pi n - \frac{5 \pi}{12}$$
$$7 x = 2 \pi n + \frac{7 \pi}{12}$$
Divide both parts of the equation by
$$7$$
get the intermediate answer:
$$x = 2 \pi n + \frac{5 \pi}{12}$$
$$x = 2 \pi n - \frac{7 \pi}{12}$$
$$x = \frac{2 \pi n}{7} - \frac{5 \pi}{84}$$
$$x = \frac{2 \pi n}{7} + \frac{\pi}{12}$$
The final answer:
$$x_{1} = 2 \pi n + \frac{5 \pi}{12}$$
$$x_{2} = 2 \pi n - \frac{7 \pi}{12}$$
$$x_{3} = \frac{2 \pi n}{7} - \frac{5 \pi}{84}$$
$$x_{4} = \frac{2 \pi n}{7} + \frac{\pi}{12}$$
The graph
The graph
sin(6*x)+cos(6*x)*sqrt(3)=-2*cos(8*x) equation