66883

Quantifiers

Quantifiers are symbols used instead of words "for every” and "there exists”.

V- "for every”, "for all", "for each" - universal quantifier, big quantifler.

Universal quantifier is a generalization of the conjunction:

Vxp{x) means that p(xl) Ap(x2) A... Ap{xń) is true. 3- "there exists”, "there is" - existential quantifier, smali quantifier.

Existential quantifier is a generalization of the disjunction:

3x p(x) means that p(x\) Vp(x2) l/... Vp(xn) is true. 3\ - "there exists exactly one” - special case of existential quantifier.

3\x p(x) means that there exists one and only one element

x0, for which p(x0) is true.