[Math] Is this a correct solution to determining which of two people is the liar using one question

Question

I am a newbie to Stack-Exchange and if there is any problem in my question — I apologize beforehand .

I was working my way through some Propositional Logic Questions in Discrete Maths by Rosen , when I came across the following question :

An explorer is captured by a group of cannibals. There are two types
of cannibals—those who always tell the truth and those who always lie.
The cannibals will barbecue the explorer unless he can determine
whether a particular cannibal always lies or always tells the truth.
He is allowed to ask the cannibal exactly one question.

Find a question that the explorer can use to determine whether the
cannibal always lies or always tells the truth.

My Solution :

If I were to ask you whether you are a liar, would you answer yes?

• The honest person would say NO.
• The liar would say YES (due to double negation).

Doubt :

Am I correct in saying my answer will work? It almost seems too simple.

Answer 1

You have exactly the right idea. You force the liars to make two negations. This question works just fine, as will others, as long as they are "honest" liars.