Prove Hermitian with two different wave functions

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SUMMARY

The discussion focuses on proving that the operator  is Hermitian using two different wave functions, ψ(r) = c_n ϕ_n(r) + c_m ϕ_m(r). The key equation derived is ∫ψ_m(r)^* Âψ_n(r)dr = ∫Â^* ψ_m(r)^* ψ_n(r)dr, which stems from the fundamental property of Hermitian operators. The user struggled with expanding the expressions and sought clarification on the correct approach, ultimately sharing their own solution for future reference.

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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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