Undergrad Determining coefficients from an equation with 3 variables

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The discussion centers on solving an equation related to worm gear meshing, specifically Equation 16 from a referenced paper. The equation involves three variables: l_1, θ_1, and φ_1(φ_2), but only θ_1 appears prominently, raising questions about the completeness of the equation. The user considers using Cramer's Rule to extract coefficients for a 3x3 matrix but is uncertain about the equation's structure and whether it truly represents a linear system. There are concerns about potential typos in the equation, such as the relationships between γ_1 and θ_1, and 1 and l_1. Clarification on these points is sought to proceed with the solution.
RichardWattUK
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Determining coefficients from an equation with 3 variables
Hi,

Some of the background related to this question is in this thread, but I've got another question as I'm looking at another problem that has come up with the same application which I'm trying to solve using the equation of meshing for a worm gear and the cutting/grinding tool that creates it. This is taken from the paper "Contact Characteristics of Recess Action Worm Gear Drives With Double-Depth Teeth", which you can view here, specifically Equation 16:

$$f(l_1,\theta_1,\phi_1(\phi_2))=\omega_1{[(m_21 cos \gamma_1-1) Y_1+m_21(cos \phi_1 sin \gamma_1 Z_1 + sin \phi_1 cos \gamma_1 C_1)]N_x1+[-(m_21 sin \gamma_1-1) X_1+m_21(-sin \phi_1 sin \gamma_1 Z_1 + cos \phi_1 cos \gamma_1 C_1)]N_y1+[m_21 sin \gamma_1(-cos \phi_1 X_1 + sin \phi_1 Y_1 + C_1)]N_z1}=0$$

This has 3 variables in it - ##l_1##, ##\theta_1##, ##\phi_1(\phi_2)## - now, some of the notation is not familiar to me since it's been about 20 years since I last studied math(s), but I've found that I may be able to use Cramer's Rule to solve for the 3 variables if I can construct a 3x3 matrix of the coefficients and a 3x1 vector for the results.

What I also find strange is there's the ##f(l_1,\theta_1,\phi_1(\phi_2))## part but the main equation only references ##\theta_1##, but since this equation is created using other equations, that could cause the loss of ##l_1## and ##\theta_1## due to the substitutions and expansions I suppose?

So, how would I solve this equation, and how would I get the coefficients from it to use with Cramer's Rule? It looks to me like a matrix system of linear equations, but is it really?
 
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The expression doesn't look right. ##\phi_1## is the only variable there.
 
mathman said:
The expression doesn't look right. ##\phi_1## is the only variable there.
I was thinking the same thing, but that's how it's written in the paper and I've been looking for an errata in case there were any corrections made since but I can't find anything.
 
It looks there may be typos like ##\gamma_1=\theta_1?## and ##1=l_1?##.
 
I am studying the mathematical formalism behind non-commutative geometry approach to quantum gravity. I was reading about Hopf algebras and their Drinfeld twist with a specific example of the Moyal-Weyl twist defined as F=exp(-iλ/2θ^(μν)∂_μ⊗∂_ν) where λ is a constant parametar and θ antisymmetric constant tensor. {∂_μ} is the basis of the tangent vector space over the underlying spacetime Now, from my understanding the enveloping algebra which appears in the definition of the Hopf algebra...

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