Hey guys, I'm doing a third year course called 'Foundations of Quantum Mechanics' and there's this thing in my notes I don't quite get. I was hoping to get your help on this, if you don't mind. It's about Hermitian conjugate operators. The sentences go (v, Au) = (A†v|u) <v|A|u> = <v|(A|u>) <v|A|u> = (<v|A)|u> (<v|A)† = A†|v> <v|A|u>*=<u|A†|v> I am wondering how the fourth line might follow from the third and if the fifth line belongs to this chunk or if it's a separate piece of info on its own. I would appreciate any form of help!