Proving Cubic Equation Theta & a,b

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    Cubic Theta
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Discussion Overview

The discussion revolves around solving a cubic equation represented by the function y=ax³+bx², where participants are trying to determine the values of coefficients a and b based on a given relationship involving an angle Theta. The inquiry seeks mathematical proof or guidance on deriving these coefficients.

Discussion Character

  • Exploratory
  • Mathematical reasoning

Main Points Raised

  • One participant presents a function y=ax³+bx² and seeks to find a and b using the equations a=(xtan(Theta)-2y)/(x³) and b=(3y-xtan(Theta))/(x²).
  • Another participant notes the lack of conditions provided for a and b, questioning the clarity of the problem.
  • A further response suggests choosing specific values for x to simplify the problem, proposing x=1 to derive a relationship between a and b.
  • There is a mention of the tangent of Theta, indicating that understanding this value may be relevant to the discussion.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the conditions or properties needed to solve for a and b, indicating that multiple views and uncertainties remain in the discussion.

Contextual Notes

The discussion lacks specific conditions or properties that a and b must satisfy, which may limit the ability to derive a unique solution. Additionally, the role of Theta and its tangent is not fully explored, leaving assumptions about its value and relevance unresolved.

agus
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Hai, I have a question solving a cubic equation. I have a function
y=ax*x*x+bx*x. I want to get a solution for the value of a and b. From reference, I found that a=(xtan(Theta)-2y)/(x*x*x) and
b=(3y-xtan(Theta))/(x*x)
[Theta] is an angle or tangent of each point x along a cubic curve or function. Could anyone guide me on how to prove this statement mathematically?
TQ
 
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You want to solve for a and b but you didn't provide any conditions on them.
 
agus said:
Hai, I have a question solving a cubic equation. I have a function
y=ax*x*x+bx*x. I want to get a solution for the value of a and b. From reference, I found that a=(xtan(Theta)-2y)/(x*x*x) and
b=(3y-xtan(Theta))/(x*x)
[Theta] is an angle or tangent of each point x along a cubic curve or function. Could anyone guide me on how to prove this statement mathematically?
TQ

It is not at all clear what you want to do. Find values of a and b so that y= ax3+ bx2 has what properties??
 
Well, anyway, from what you are saying, if we can choose values of X, just let X=1, giving Y=a+b. Then use a second value. Tangent of Theta? It might help to find out what that is.
 

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