How to Solve K'(T) = k(M-K(t)) Using Given Values?

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Discussion Overview

The discussion revolves around solving the ordinary differential equation (ODE) K'(T) = k(M - K(t)) using specified values. Participants explore the definitions of the variables involved and the implications of the given conditions on the solution process.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant expresses uncertainty about how to begin solving the equation and proposes specific values for M, K(0), and K(2).
  • Another participant suggests that the problem is an ODE modeling question and requests clarification on the definitions of K, k, T, and t, particularly whether K'(T) refers to dK/dt or dK/dT.
  • A participant defines K(t) as the total knowledge about performing a task at time t and states that K'(t) represents the rate of change of K(t), which is proportional to the knowledge yet to be acquired.
  • One participant concludes that M is a constant and assumes T and t are equivalent, noting that k is an unknown constant. They reformulate the equation as a first-order separable ODE and suggest solving it for K(t) using the provided initial conditions.

Areas of Agreement / Disagreement

Participants generally agree on the nature of the equation as an ODE and the role of M as a constant. However, there is no consensus on the definitions of the variables or the initial approach to solving the equation, indicating multiple competing views remain.

Contextual Notes

Participants have not fully clarified the relationships between the variables K, k, T, and t, leading to potential ambiguities in the interpretation of the ODE. The assumptions about the constancy of M and the equivalence of T and t are also not universally accepted.

chaotixmonjuish
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I'm not even sure how to start this question

K'(T)=k(M-K(t))
M=total knowledge

suppose that:
M=100
K(0)=0
and
K(2)=50

does this mean
k'(0)=k(100-0)
and
k'(2)=K(100-50)
 
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This looks like one of those ODE modeling questions. I think you have to elaborate more on what K, k, T and t are. More specifically tell us which variables the aforementioned functions are of. And K'(T) is dK/dt or dK/dT ?
 
K(t)is the total knowledge about how to perform at task at time t

K'(t) or the rate of change in K(t) is proportional to what we do not know yet or
K'(t)=k(M-K(t)) where M is total knowledge

it takes two years to learn 50% of the task, how long does it take to learn 75%
 
Ok I take it that M is a constant and not a function of t and T and t are the same thing. k is also an unknown constant. So you have:

[tex]\frac{dK}{dt} = k(M-K)[/tex]

So this is a 1st order ODE. It's clearly separable. Solve it for K(t) and plug in the given values of K(0) and K(2) to solve for the constant of integration and k.
 

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