Difference between revisions of "Dynamic equation"

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(Examples of Dynamic Equations)
(See Also)
 
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Dynamic equations are analogues of differential equations on a [[time scale]]. If we have $\mathbb{T}=\mathbb{R}$ then the resulting theory of dynamic equations is the thoery of differential equations. If $\mathbb{T}=h\mathbb{Z}$ then the resulting theory of dynamic equations is the theory of difference equations of stepsize $h$.  
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Let $\mathbb{T}$ be a [[time scale]]. Dynamic equations are a generalization and extension of [[differential equation|differential equations]] and [[difference equation|difference equations]].
  
Suppose that $f \colon \mathbb{T} \times \mathbb{R}^2 \rightarrow \mathbb{R}$. Then the equation
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=See Also=
$$y^{\Delta} = f(t,y,y^{\sigma})$$
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[[Delta exponential dynamic equation]]<br />
is called a first order dynamic equation. Our goal is generally to find all functions $y \colon \mathbb{T} \rightarrow \mathbb{R}$ that satisfies the equation.
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[[First order dynamic equations]]<br />
 
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[[Second order dynamic equations]]<br />
Suppose there are [[continuity | rd-continuous]] functions $p_i \colon \mathbb{T} \rightarrow \mathbb{R}$. Define the operator
 
$$Ly=y^{\Delta^n}+\displaystyle\sum_{k=1}^n p_i y^{\Delta^{n-i}}.$$
 
We say that the equation $Ly=f$ is an $n$th order dynamic equation.
 
 
 
==Examples of Dynamic Equations==
 
*The [[Exponential_functions | exponential functions]] are defined by the initial value problem, for [[Regressive_function | regressive]] $p$: for $s,t \in \mathbb{T}$,
 
$$y^{\Delta}(t)=p(t)y(t); y(s)=1.$$
 

Latest revision as of 16:32, 9 February 2017

Let $\mathbb{T}$ be a time scale. Dynamic equations are a generalization and extension of differential equations and difference equations.

See Also

Delta exponential dynamic equation
First order dynamic equations
Second order dynamic equations