Question in variational method (QM)

Safinaz
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Homework Statement



Hi, in this book " [Nouredine_Zettili]_Quantum_Mechanics_Concepts ", Eq. (9.133)

Homework Equations



I don't know how the second line

upload_2015-9-11_1-25-15.png


had come from the first line:
upload_2015-9-11_0-42-50.png

The Attempt at a Solution

I got only two terms such that:

$$ < \psi_0| H | \psi_0 > = A^2 \int^{+\infty}_{-\infty} \Big( - \frac{2\alpha^2 h^2}{m} e^{-2\alpha x^2} + \frac{1}{2} m \omega^2 x^2 e^{-2\alpha x^2} \Big) dx $$So what I missed ?
 

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Last edited:
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I fixed the images in your post.

The first derivative of ##e^{-\alpha x^2}## gives ##-2\alpha x e^{-\alpha x^2}##, the second derivative leads to ##(-2\alpha + 4\alpha^2 x^2) e^{-\alpha x^2}## and the second summand should give the missing term.
 
Yap ..
 
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