COMP 232 Lecture Notes - Lecture 4: International Securities Identification Number, Prime Number, Pus

• School: Concordia University
• Department: Computer Sci.
• Course: COMP 232
• Professor: Gosta Grahne

Document Summary

Let r(x, y) be the predicate x2 x + y. R(5, 2) 52 5 + 2 true. R(0, 2) 02 0 + 2 false. We need multiple quanti ers to turn a proposi- tional function of many variables into a propo- sition. When there are multiple quantifers, they should be read from left to right. X y r(x, y) x y r(x, y). For every x there exists some y such that r(x, y). R(x, y) =def x2 x + y. Changing the order of the quanti ers may change the proposition. Note that xr(x, y) or xr(x, y) are proposi- tional functions of one variable (the free vari- able y). For every integer x there exists an integer y greater than x. There is an integer y that is larger than any other integer. Quanti ers of the same type can be reversed without changing the truth value, i. e. ,