Final answer:
The task is to solve the trigonometric equation involving cotangent, cot 2x + cot x = 3. It will require the application of trigonometric identities to simplify and solve for x, but there is unrelated information provided that does not aid in solving this particular equation.
Step-by-step explanation:
The question provided seems to be about solving a trigonometric equation for x. The equation cot 2x + cot x = 3 involves trigonometric functions and will require the use of trigonometric identities to solve. Typically, this would involve transforming the cotangent functions into expressions involving sine and cosine, using the identity cot θ = 1/tan θ = cos θ/sin θ, or using sum and product identities for cotangent.
However, the information provided contains several unrelated formulae and notations that do not pertain to the resolution of the original cotangent equation. It is possible that they are from different parts of a broader context of physics or mathematics problems involving quadratic equations or conservation of momentum, but they do not directly facilitate the solving of the trigonometric equation in question.