Help with Equation 9.25 in Srednicki's QFT Book?

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Can anybody help me out with equation 9.25 in Srednicki's QFT book?

He says the in the eq. 9.25 an integration by parts has been carried out. I do not see how. I guess we integrate 9.9 and get then 9.25 somehow, but how? Any hints?

thank you
 
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Yes, starting with 9.9,
-{1\over2}\int d^4x(A\partial^\mu\varphi\partial_\mu\varphi+Bm^2\varphi^2)
we partially integrate to move \partial^\mu from the first \varphi to the second, which results in
-{1\over2}\int d^4x(-A\varphi\partial^\mu\partial_\mu\varphi+Bm^2\varphi^2)
Then we replace fields by functional derivatives in the way that's done throughout section 9.
 
Thanks so much, Avodyne! You are the Srednicki guy, who never let's us down. I rather randomly pick up the book when I'm in the mood to learn some QFT. Well, and as it is, I always quickly stumble upon some equations I don't understand. So thanks so much for the help, because I really want to learn QFT, no matter what!
 
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