Prove Hermitian with two different wave functions

pfollansbee
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Homework Statement



Let ψ(r)= c_n ϕ_n (r) + c_m ϕ_m (r) where ϕ_n(r) and ϕ_m (r) are independent functions.
Show that the condition that  is Hermitian leads to
∫ψ_m (r)^* Âψ_n (r)dr = ∫Â^* ψ_m (r)^* ψ_n (r)dr

Homework Equations



∫ψ(r)^*  ψ(r)dr = ∫Â^* ψ(r)^* ψ(r)dr

The Attempt at a Solution



It is obvious to me that if
<m|\hat A|n> = <\hat A m|n>
then
<m|\hat A|n> = <n|\hat A|m>^*

My professor gave me a hint and said that I need to expand these out and show that they are equal. This is where my problem lies. I have no idea how to expand these out. I have tried a few ways, like setting
\phi _m = (\psi -c_n \phi _n)/c_m
This certainly did not seem like the correct approach to me.

Maybe someone here can give me another hint as to how this goes. I have asked my professor three times to talk to me about it, but he seems content in misunderstanding me and talking about other problems that we have already solved.
 
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Hmm no replies... oh well. Here is the solution that I came up with. Just in case anyone else happens to happen upon a similar problem, this may help.
 

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