This deduction is baseless, there is no reason to think an LLM will only hallucinate on complex topics. They still get the "number of es in seventeen" question wrong regularly. The kind of mistakes an LLM makes has no clear resemblance to the kind of mistakes a human makes, because they are not doing the same thing.
And for the harder maths you want something not just to explain the answer but to diagnose your conceptual error behind your questions. Asking the teacher after class or tutorial type systems work efficiently for a reason.
