What is the meaning of "で" in this sentence? Looks like the same function of から but I'm not sure...
Japanese Language Stack Exchange is a question and answer site for students, teachers, and linguists wanting to discuss the finer points of the Japanese language. It only takes a minute to sign up.Sign up to join this community
It can help if you think about で particle as options. There are different locations, ways to do something, reasons and so on. With で particle we describe or clarify which one it is, in which exactly manner we do it, it's done to us or something happens generally depending on our control over such action. In such case we talk about smiling and we can smile in many different ways too.
呆れた顔で微笑む means to do 微笑む with 呆れた顔 option. "To smile with dismay face".