- #1
FrogPad
- 810
- 0
We are now studying the one space dimension heat equation [itex] u_t = u_{xx} [/tex]
The fundamental solution is given as:
[tex] u(t,x)=\int_{-\infty}^{\infty} \frac{1}{2\sqrt{\pi t}}e^{-(x-y)^2/4t}u_0(y)dy [/tex]
I don't understand where the [itex] y [/itex] comes from.
The example in this section is:
If [itex] u_0(x)=1 [/itex], the temperature stays at [itex] u =1 [/itex] for all [itex] t [/itex].
I wish I could see the solution, instead of just the answer. But that's the style of the book. I just don't see how to go from the fundamental solution, to the answer.
The fundamental solution is given as:
[tex] u(t,x)=\int_{-\infty}^{\infty} \frac{1}{2\sqrt{\pi t}}e^{-(x-y)^2/4t}u_0(y)dy [/tex]
I don't understand where the [itex] y [/itex] comes from.
The example in this section is:
If [itex] u_0(x)=1 [/itex], the temperature stays at [itex] u =1 [/itex] for all [itex] t [/itex].
I wish I could see the solution, instead of just the answer. But that's the style of the book. I just don't see how to go from the fundamental solution, to the answer.