$$\frac{d\langle p\rangle}{dt}=-i\hbar \int_{-\infty}^{\infty}\frac{d\psi^*}{dt} \frac{d\psi}{dx}+\psi^*\frac{d}{dt}\Bigr(\frac{d\psi}{dx}\Bigr)$$ I didn't know the coding of partial derivative which are inside the integral There is a question about this on site, but I don't have much experience with bra -ket notation. Ehrenfest's theorem derivation. The first integrand makes sense but I'm completely at odds with the second one