I sometimes find potential errors in slides/notes that professors provide us as studying material. These are often some distraction or algebraic errors, other times lack of formalism that might generate misunderstanding.
As a PhD student, should I let them know, so that they can correct themselves in the case that my intuition was correct?
Sometimes I am not 100% sure of my claim and I would find it interesting just to know how right/wrong I am. Others I would like to appear kind, if they were interested in polishing their notes. However, I am afraid that professors might take it as a challenge, and therefore I would like to know to which extent this is appropriate.