1. While solving, pay careful attention to phrases like and, or, […] The concept of set serves as a fundamental part of the general mathematics of day-to-day needs. Basic Concepts of Set Theory. Sets and Venn diagrams is one of the easiest topics of CAT. In this topic, we will discuss the Sets Formula … Theorem 1.4. Let Aand Bbe sets. theory that: 1) you’ll be familiar with basic set theoretic notation and where it comes from; and 2) you’ll gain some familiarity with powerful set theoretic tools which can make light work of logical problems in the truth literature. Let xbe arbitrary. Set Theory is a branch of mathematics which deals with the study of sets or the collection of similar objects. Theorem: S S • Any set S is a subset of itself Proof: • the definition of a subset says: all elements of a set A must be also elements of B: x (x A x B). … • Applying this to S we get: • x (x S x S) which is trivially True • End of proof Note on equivalence: • Two sets are equal if each is a subset of the other set. each formula θ(x¯) of L 2 we have T 1 ‘ ∀x¯(θ(x¯)f ↔ θ(x¯)g). The emphasis should be made while translating the sentences into areas of the Venn diagram. The notion of set is taken as “undefined”, “primitive”, or “basic”, so we don’t try to define what a set is, … Sets and elements Set theory is a basis of modern mathematics, and notions of set theory are used in all formal descriptions. Rosen uses the latter, but the former is actually more standard.) Set Theory Problems Prof. Joshua Cooper, Fall 2010 Determine which of the following statements are true and which are false, and prove your answer. 1.1. An(B[C) = (AnB) \(AnC) Proof. In particular, for each sentence σ of L 2, T 1 ‘σf if and only if T 1 ‘σg. 1. Set theory is one of the most fundamental branch of mathematics, But is also also very complex if you try to analyze three or more sets. The set theoretic di erence AnBis de ned by x2AnBi x2Aand x62B. Today this concept is being used in many branches of mathematics. Set theory has its own various notations and symbols that may seem sometimes unusual for many. (NB: The symbol ‘n’ has the same meaning as ‘ ’ in the context of set theory. 3 The Ackermann interpretation By ZF−inf we mean the theory in the ﬁrst-order language L ∈ of set theory with all the usual axioms of ZF except inﬁnity, which is negated. Most of the Set Thoery formulas of CAT in this section can be deduced logically with little effort. When we discuss formulas later in the course, ... A set is completely determined by the elements and we de ne equality on sets as follows: De nition 2. Then x2An(B[C) i x2Aand x62B[C i x2Aand not (x2Bor x2C) i x2Aand (x62Band x6inC) i x2Aand x62Band x6inC i x2Aand x62Band x2Aand x6inC i x2(AnB) and x2(AnC) i x2(AnB) \(AnC) Provisional de nition of function: Let A;Bbe sets.