Frequent mistakes of students
In example 1a) we find next mistakes:
Wrong negation of first quantifier: There does not exist any state, in which every law is at
least two times revised. (Zuzana). The students negated only the first quantifier, but they
haven't the negation of complex proposition.
Wrong negation of second quantifier: In each state is every law at most one times revised.
(Júl