Find Lambda from this arbitrary triangle

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    Lambda Triangle
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Discussion Overview

The discussion revolves around deriving a specific equation related to angles and magnitudes in a triangle, particularly focusing on the calculation of the angle lambda (λ) from a given schematic. Participants are exploring methods to manipulate equations and visualize the triangle to find the desired relationships.

Discussion Character

  • Exploratory, Technical explanation, Mathematical reasoning

Main Points Raised

  • One participant expresses confusion about obtaining a specific equation from a schematic and seeks guidance on resources for learning about angles and magnitudes in complex schematics.
  • Another participant suggests manipulating an equation involving sine and cosine to visualize the triangle relevant to calculating tan λ.
  • A different participant shares their progress and an attachment, indicating their current understanding of the problem.
  • One participant acknowledges the previous work but notes that it does not directly lead to the desired tan λ formula, recommending the construction of a right triangle to facilitate the calculation.
  • A later reply claims to have found a solution by extending a segment to form a right triangle, asserting that the tangent of lambda is now clear.

Areas of Agreement / Disagreement

Participants appear to be working towards a solution with some shared understanding of the geometry involved, but there is no explicit consensus on the methods or final formula for tan λ.

Contextual Notes

Some participants' approaches depend on specific assumptions about the triangle's configuration and the relationships between the angles and sides, which may not be universally agreed upon.

bugatti79
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Folks,

I am puzzled how one obtains equation 3.2.31 based on the schematic as attached! Can you help?
Is there an online source I can refer to to learn how to obtain angles and magnitudes of complex schematics?

Thanks
 

Attachments

  • Schematic.jpg
    Schematic.jpg
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I am still working on this one...
However, I feel like the secret will be in manipulating the equation you have.
Edited*
##\frac{\sin \psi }{ m - \cos \psi } = \frac{\sin( \pi - \psi) }{ a/p +\cos( \pi - \psi) } = \frac{p\sin( \pi - \psi) }{ a + p \cos ( \pi - \psi) }##
This should help you visualize the triangle you should be working with for ##\tan \lambda##.
 
Last edited:
Hi, thanks...
This is as far as I got...see attached...
 

Attachments

  • Schematic 2.jpg
    Schematic 2.jpg
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That looks good. You extension works to give you a solution for lambda. But it doesn't help get to that tan lambda formula you were looking for.

Try to extend the side length a to make a right triangle with hypotenuse of p. Use sin and cos to determine the side lengths.
Then you can directly get the formula for tangent using the opposite/adjacent of the appropriate right trangle which includes angle lambda.
 
Hi RUber,

I have it. The extended segment of "a" which forms a right angled triangle with P is Pcos(pi-psi). The tan of lambda is obvious. Thank you very much.
I have learned a new way of tacking triangles!
 
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