Solving a Trigonometry Problem: Find u(x,t) Polynomial

[MIXA066]

<Moderator's note: Moved from a technical forum and thus no template.>

Task: http://snk066.tk/math/Task.png
My solution: http://snk066.tk/math/my_solution.jpg
What you need to? I need an answer in the form: u (x,t) = (some polynomial)
The solution is not really necessary, if someone will explain-thank you, but if there are calculators that believe this, one answer will do.
I tried to decide for myself, it did not work. The problem consists in obtaining the values of the constants. The integration and expression of these constants, where is trigonometry, they're just not expressed, maybe under the cosines of the bad roots.

 

[Ray Vickson]

<Moderator's note: Moved from a technical forum and thus no template.>

Task: http://snk066.tk/math/Task.png
My solution: http://snk066.tk/math/my_solution.jpg
What you need to? I need an answer in the form: u (x,t) = (some polynomial)
The solution is not really necessary, if someone will explain-thank you, but if there are calculators that believe this, one answer will do.
I tried to decide for myself, it did not work. The problem consists in obtaining the values of the constants. The integration and expression of these constants, where is trigonometry, they're just not expressed, maybe under the cosines of the bad roots.

If you really do want help you should type out your solution; the images you posted are unreadable on my screen. Read the PF Guidelines.

 

[Mark44]

Thread closed. It's very difficult to read the solutions image. Please post your work inline, not as an image. See our tutorial on LaTeX here https://www.physicsforums.com/help/latexhelp/.