Uniqueness of solution based on characteristic curves











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I have a pde
$$begin{cases} u_t − xu_x = 2u & xinmathbb{R}, t>0\
u(x, 0) = frac{1}{1+x^2}
end{cases}$$



I've solved it using method of characteristics ($u=frac{1}{1+x^2e^{2t}}e^{2t})$ and plotted charactersitic curves.enter image description here



Consider the upper half-space since $t>0$.
How to argue using the drawing whether or not it is the unique solution? Thank you.










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  • Are you plotting in the $(t, u)$ plane? $(x, u)$? $(t, x)$?
    – Mattos
    Nov 19 at 1:46












  • @Mattos This is the projection on the $(x,t)$-plane
    – dxdydz
    Nov 19 at 2:01

















up vote
2
down vote

favorite
1












I have a pde
$$begin{cases} u_t − xu_x = 2u & xinmathbb{R}, t>0\
u(x, 0) = frac{1}{1+x^2}
end{cases}$$



I've solved it using method of characteristics ($u=frac{1}{1+x^2e^{2t}}e^{2t})$ and plotted charactersitic curves.enter image description here



Consider the upper half-space since $t>0$.
How to argue using the drawing whether or not it is the unique solution? Thank you.










share|cite|improve this question






















  • Are you plotting in the $(t, u)$ plane? $(x, u)$? $(t, x)$?
    – Mattos
    Nov 19 at 1:46












  • @Mattos This is the projection on the $(x,t)$-plane
    – dxdydz
    Nov 19 at 2:01















up vote
2
down vote

favorite
1









up vote
2
down vote

favorite
1






1





I have a pde
$$begin{cases} u_t − xu_x = 2u & xinmathbb{R}, t>0\
u(x, 0) = frac{1}{1+x^2}
end{cases}$$



I've solved it using method of characteristics ($u=frac{1}{1+x^2e^{2t}}e^{2t})$ and plotted charactersitic curves.enter image description here



Consider the upper half-space since $t>0$.
How to argue using the drawing whether or not it is the unique solution? Thank you.










share|cite|improve this question













I have a pde
$$begin{cases} u_t − xu_x = 2u & xinmathbb{R}, t>0\
u(x, 0) = frac{1}{1+x^2}
end{cases}$$



I've solved it using method of characteristics ($u=frac{1}{1+x^2e^{2t}}e^{2t})$ and plotted charactersitic curves.enter image description here



Consider the upper half-space since $t>0$.
How to argue using the drawing whether or not it is the unique solution? Thank you.







pde






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asked Nov 18 at 22:38









dxdydz

1169




1169












  • Are you plotting in the $(t, u)$ plane? $(x, u)$? $(t, x)$?
    – Mattos
    Nov 19 at 1:46












  • @Mattos This is the projection on the $(x,t)$-plane
    – dxdydz
    Nov 19 at 2:01




















  • Are you plotting in the $(t, u)$ plane? $(x, u)$? $(t, x)$?
    – Mattos
    Nov 19 at 1:46












  • @Mattos This is the projection on the $(x,t)$-plane
    – dxdydz
    Nov 19 at 2:01


















Are you plotting in the $(t, u)$ plane? $(x, u)$? $(t, x)$?
– Mattos
Nov 19 at 1:46






Are you plotting in the $(t, u)$ plane? $(x, u)$? $(t, x)$?
– Mattos
Nov 19 at 1:46














@Mattos This is the projection on the $(x,t)$-plane
– dxdydz
Nov 19 at 2:01






@Mattos This is the projection on the $(x,t)$-plane
– dxdydz
Nov 19 at 2:01

















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