Can x = t - sin(t) be expressed in terms of t?

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Discussion Overview

The discussion revolves around the possibility of expressing the equation x = t - sin(t) in terms of t. Participants explore the implications of this relationship, particularly in the context of parametric equations and graphical representation.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant expresses uncertainty about whether a closed form for t can be derived from x = t - sin(t), noting an infinite regression when attempting to isolate t.
  • Another participant asserts that there is no closed form available and questions the origins of x and t.
  • A participant mentions a related equation y = 1 - cos(t) and discusses challenges in converting parametric equations to rectangular form, indicating a broader context of calculus and graphing.
  • One participant clarifies the parametric curve representation and suggests a method to express t in terms of y, while questioning the necessity of solving for t in this context.
  • A participant acknowledges the difficulty in expressing y in terms of x and expresses a desire to learn more about potential mathematical techniques that could simplify the problem.

Areas of Agreement / Disagreement

Participants generally agree that expressing t in terms of x is challenging and may not be possible in a closed form. However, there are multiple perspectives on the necessity and implications of solving for t.

Contextual Notes

Participants mention the dependence on specific definitions and the context of calculus, particularly regarding parametric and rectangular forms. There are unresolved mathematical steps related to the transformations discussed.

AnotherParadox
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Sorry title should say x=t-sin(t) in terms of t...Is it possible? I get close.. I do t = x + sin(t) and use the relation again to get an infinite regression

T = x + sin(x +sin(x + sin(x + sin(x... ))))
I'm not sure if it has a real limit or simplification ... anyone know?
 
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There is no closed form you are looking for. What is it all about and where are ##x## and ##t## from?
 
fresh_42 said:
There is no closed form you are looking for. What is it all about and where are ##x## and ##t## from?
I also have y=1-cos(t).. it's a position vector for a Cal III course practice. I'm able to graph in parametric but rectangular has me stumped since I can only put it in terms of x and not y. I have the problem done and everything I'm just curious about this particular aspect
 
So, if I got you right (and made no mistake), you have a parametric curve ##t \mapsto \begin{pmatrix} t - \sin t \\ 1 -\cos t \end{pmatrix}##, i.e. a map ##I \rightarrow \mathbb{K}^2## where ##I## is a real interval and ##\mathbb{K}## either the real or complex numbers. Why do you want to solve this for ##t##?
Of course you could always write ##t = \arccos(1-y) \; , \; x= \arccos(1-y) - \sqrt{2y - y^2}## to get rid of the parameter ##t## and deal with the domains, where this is true. But why?
 
Yea you got it. I was able to write in terms of x too but not y which is what I need to graph it properly without parametric which is sort of the reason. The real reason is because I wanted to learn something new but it seems like my suspicion is being confirmed that it can't really be done unless there is some crazy math out there we don't know about to reduce or simplify...
 

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