(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

http://img42.imageshack.us/img42/1082/clipboard01lx.jpg [Broken]

2. Relevant equations

(see solution)

3. The attempt at a solution

I literary just spent 5 hours trying to apply those boundary conditions, trying exponentials, sines, cosines, hyperbolic function etc... I always get complex numbers in the final solution :( but it's not physical to get complex numbers there :(

Note: A_{w}and B_{w}are just constants (w is an index).

http://img189.imageshack.us/img189/4475/94889151.jpg [Broken]

Any ideas where I went wrong? General solution seems fine, maybe I'm misunderstanding the boundary conditions? And in my final answer I tried expanding [tex]\sqrt{i}=\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{2}}i[/tex] and then using cos(A+B) formula and writing the result using hyperbolic sines and cosines, but it's still complex :(

Thanks

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# Homework Help: Heat diffusion equation solutions for semi-infinite slab

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