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How do I solve this integral (expectation value) : $$\int_{-\infty}^{\infty} \psi (x)^* \hat p \psi (x)\ dx.$$ where the $\hat p =-i\hbar \frac {\partial}{\partial x}$ is an operator and $\psi (x)$ is wave function.

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Where are you stuck? –  Chris Gerig Jun 14 '12 at 21:17
@Chris Gerig exactly here $\langle \hat p \rangle$ –  user29646 Jun 14 '12 at 21:22
Just a note: one solves equations and evaluates integrals. –  Joe Jun 14 '12 at 22:08
You can't solve this and can't evaluate this integral unless wave function is not specified. In fact you are asking a regular method of evaluation average pulse for all possible wave functions, i.e. for all possible quantum systems! –  userNaN Jun 14 '12 at 22:12

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