ODE Existence/Uniqueness Intervals

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SUMMARY

The discussion focuses on determining the intervals for the existence of a unique solution to the differential equation dy/dx = e^-(y-x)^2 with the initial condition y(0) = 0. It is established that both the function and its partial derivative are continuous, confirming the existence of a unique solution. The interval for existence is defined as [0, t*], where t* is calculated as b/(max|f(x,y)|). The maximum value of f(x,y) is simplified by substituting p = y - x, leading to the conclusion that the maximum of e^(-p^2) can be easily determined.

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Homework Statement



Obtain intervals x∈[0,α] for the existence of a unique solution

dy/dx = f(x,y) = e^-(y-x)^2; y(0) = 0

on the rectangle B = [0,a]x[-b,b]

Homework Equations


The Attempt at a Solution



Since both dy/dx and it's partial derivative of y are both continuous, a unique solution exists. Thus an interval for existence for t is [0,t*], where t* = b/(max|f(x,y)|).

I'm not sure how to determine max|f(x,y)|.

Any help is appreciated.
 
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f(x,y) = e^(- (y-x)^2), correct? In that case, it seems to me that it would be easier to temporarily define a new variable, say, p = y-x, and substitute that in. From there, it's easy to find the maximum value of e^(-p^2).
 

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