How to respond to nagging followup questions after answering a question

Question

I've had the experience about five times recently when after I answer a question, the asker ends up nagging me with more questions in the comments. The most recently was just now: Exercise $14$, section $2.C$ - Linear Algebra Done Right. I suspect that the person asking the question has not really made enough effort.

I can't be the only person who has experienced this.

What is the appropriate response to nagging questions like this? I usually tell them to ask another sitewide question as you can see above, but it's irritating enough to me when these endless followup questions start that several times I have considered just deleting the answer.

Addendum

After I posted this question, the questioner deleted the bulk of their comments, so I'd like to summarise the deleted discussion.

The questioner used a dubious method of proof, so I'd suggested using a different method to solve the problem, based on induction.

The questioner was not familiar with induction, and trying to explain mathematical induction to someone from scratch in the comments seemed a rather exhausting thing to do, so I suggested they ask another question about it.

Then it got very annoying. The questioner started posting "solutions" consisting of some equations and some phrases from the Wikipedia article on mathematical induction or a similar text, in a "monkey-see-monkey-do" fashion, very clearly not understanding the principle at work, and then asking me if they'd got it right, repeatedly.

I don't want to offend this poster nor do I want to hurt their feelings, but at some point it's necessary to put the brakes on, and there doesn't seem to be any mechanism to stop people from doing this kind of pestering behaviour beyond telling the person to get lost or ignoring them.

This is not the first time I've had this experience where the questioner asks a series of exhausting and silly questions in the comments under an answer.]

Answer 1

Person asked once. We replied. They ask more.

Trick is to stop at the first instance.

If anyone is asking a separate question in comment, we need to state, "Please open a separate thread for this," even if the question is easy. Building this habit is important for us too so that we don't get irritated enough to delete our own answers.

Answer 2

I'm unaware of any "official" way to deal with this issue. Note I've also encountered similar situations on several occasions, and I did once actually just delete my answer when I became particularly annoyed (although a diamond moderator undeleted it later).

I believe requesting that they just post another question is a reasonable thing to do, as you did in your comment to your example answer. I've also done this a few times myself when the OP starts to asks about issues (usually generalizations) that are not part of the original question (and I've confirmed on several occasions that the OP did actually ask a new question).

Also, although I've not done this myself yet, I've seen several answers where, after being asked so many questions in the comments, it appears the answer author just simply stops responding (note they sometimes leave a final comment explicitly stating they will no longer reply). Keep in mind that we are all volunteers here, with nobody really required to do anything in particular, including responding to comments to them. Nonetheless, doing so is generally the polite & appropriate thing to do, and I believe it should be done in possibly all but certain more difficult cases.