I know this is an easy question but I want to confirm that I've got this right.(adsbygoogle = window.adsbygoogle || []).push({});

The wavefunction [tex]\psi(r)[/tex] can be expressed as a linear sum of orthonormal eigenfunctions [tex]\phi_n(r)[/tex] by

[tex]\psi(r) = \sum a_n\phi_n(r)[/tex].

Derive an expression for the coefficients [tex]a_n[/tex].

I think the answer is [tex] a_n = <\phi_n|\psi>[/tex] but this seems a little too easy.

Opinions?

Thanks,

C.

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# Very very very easy quantum exam question

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