Also related, I had a psychology teacher with a PhD in psychology. But because in German schools, you need to teach two subjects (with the exception of the arts), he also taught physics. He was a terrible physics teacher, but a pretty good psychology one.

I do understand it differently, but I don’t think I misunderstood. I think what they meant is the physicist notation I’m (as a physicist) all too familiar with:

∫ f(x) dx = ∫ dx f(x)

In this case, because f(x) is the operand and ∫ dx the operator, it’s still uniquely defined.

That reminds me of a story my bachelor’s supervisor in astrophysics told me: One of his best PhDs applied at an insurance company. They got an Excel sheet with data that they had 1 week to analyze. All the other applicants took the whole week. He just put it in Python, solved it in a few hours, and got the job.

I’d say the $\int dx$ is the operator and the integrand is the operand.

I think you mean operator. The operand is the target of an operator.

If they’re really, really good.

Here in Munich, our public transport is much better than any American city, but I still hate taking the train in summer. AC either does not exist or is far too weak. Taking the car takes 40, maybe 50 minutes, the train 1h25min. I still take the train, mind you, but it’s so much more exhausting than the car…

I have to mention my daily commute is between two cities outside Munich.