Prenex normal form A wff a of 8 is in prenex normal form iff 1. no vacuous quantifier occurs in A, and 2. no quantifier in A occurs in the scope of a propositional connective of A If b is in prenex normal form such that卜A≡B,We shall say that b is a prenex normal form of a Logic in Computer Science-p. 4/9Prenex Normal Form A wff A of E is in prenex normal form iff 1. no vacuous quantifier occurs in A, and 2. no quantifier in A occurs in the scope of a propositional connective of A. If B is in prenex normal form such that ` A ≡ B, we shall say that B is a prenex normal form of A. Logic in Computer Science – p.4/9