Thank you very much for your help Chisigma. I e-mail my professor with regards to this question and she only replied me her answer which is :
https://www.physicsforums.com/attachments/514._xfImport
I understood your working but my professor claim that the above is the correct answer and now I...
Have been trying for hours but simply no results. Hope that someone can help me out.
\[\frac{\partial u}{\partial t}=4\frac{\partial^2 u}{\partial x^2}\]
for \(t>0\) and \(0\leq x\leq 2\) subject to the boundary conditions
\[u_x (0,t) = 0\mbox{ and }u(2,t) = 0\]
and the initial condition...