I Find the only periodic solution of an ODE

AI Thread Summary
The discussion focuses on finding the periodic solution for the ordinary differential equation (ODE) y' + y = b(x), where b(x) is a periodic function with a specific behavior over the interval. The general solutions for the ODE are given as y(x) = exp(-x)Β·c + 1 and y(x) = exp(-x)Β·c - 1. A key challenge is determining the constant c to ensure the solution is periodic with a period of 2T while maintaining continuity. The conversation reveals confusion about the continuity of the solution and the implications of the chosen values for c. The participants emphasize the importance of continuity in the solution and how it affects the periodicity of the function.
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Find the only periodic solution for 𝑦′+𝑦=𝑏(π‘₯) with 𝑏:ℝ→ℝ has a period of 2𝑇 and is 1 for π‘₯(0,𝑇) and βˆ’1 for π‘₯(βˆ’π‘‡,0).
Find the only periodic solution for 𝑦′+𝑦=𝑏(π‘₯) with 𝑏:ℝ→ℝ has a period of 2𝑇 and is 1 for π‘₯(0,𝑇) and βˆ’1 for π‘₯(βˆ’π‘‡,0).

The ODE is easy to solve: 𝑦(π‘₯)=exp(βˆ’π‘₯)⋅𝑐+1 and 𝑦(π‘₯)=exp(βˆ’π‘₯)β‹…π‘βˆ’1. But how can I find the 𝑐 such that the solution is periodic with a period of 2𝑇?

The solution is: https://i.stack.imgur.com/S21Ze.png

Thanks for your help.
 
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sorry forgot to mention the function should be continuous.
 
but for c = 0 you won't have a continuous solution
 
it jumps frome -1 to 1?
 
Sorry I misread your question. You are right. Deleting all my previous comments...
 
Well, you have two values given, that gives you ranges to play with, continuity will determine the prefactors.

I'm not sure if I understand your notation, however. Why does x depend on two parameters?
 
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