memorized is a powerful word. Because using the Collections methods is not about memorizing their signatures. The new exam avoids having questions where the answer is based on you memorizing the signature of a method.
But to answer your question, what are the purposes of the Collections class? and that is what you should need to know for the exam.
I actually mean for you to post what you think are the purposes? It wasn't a hypothetical question.
I believe you answered my question. I meant do we need to know some of the method signatures for the collection classes. I asked this query because there were some mock exams, I came across which involved questions on collection api.