Discrete mathematical conditional expressions can be expressed as (? x)(B(x)-& gt； A(x)), or (? x)(B(x)∧A(x)).

The conditional expression of discrete mathematics is that when the conditional expression is a tautology, the tautology is an implied expression, which I don't quite understand here, because the definition of tautology is that the truth value of a given propositional formula is always t, no matter how the components are assigned. From the definition of conditional expression, it can be seen that unless the truth values of its two components are limited, the conditional expression cannot be true forever, which is inconsistent with the definition of tautology.