--%>

Define Well-formed formulas or Wffs

Wffs (Well-formed formulas): These are defined inductively by the following clauses:
  
(i) If  P  is an n-ary predicate and  t1, …, tn are terms, then P(t1, …, tn) is a wff. (Such a wff is atomic.)

(ii)  If α is wff, then ¬ α is a wff.
  
(iii)  If α and β are wffs, then α → β is a wff.  
 
(iv) If α is a wff and x is an individual variable then

1946_v.jpg

is a wff. 
 
The connectives are operators, which act on wffs, yielding other wffs; ¬ is a unary operator (it acts on a single wff), → is a binary operator. Also a quantifier, coupled with a variable, is a unary operator that acts on wffs. We require that any wff that is thus generated has a unique decomposition into components. The notation should be such as to yield a unique readability theorem.

   Related Questions in Mathematics

  • Q : First-order formulas over the

    Consider the unary relational symbols P and L, and the binary relational symbol On, where P(a) and I(a) encode that a is apoint and a (sraight) line in the 2-dimensional space, respectively, while On(a,b) encodes  that a is a point, b is a line, and o lies on b.

  • Q : Who derived the Black–Scholes Equation

    Who derived the Black–Scholes Equation?

  • Q : Problem on augmented matrix Consider

    Consider the following system of linear equations.  (a) Write out t

  • Q : Explain lognormal stochastic

    Explain lognormal stochastic differential equation for evolution of an asset.

  • Q : Examples of groups Examples of groups:

    Examples of groups: We now start to survey a wide range of examples of groups (labelled by (A), (B), (C), . . . ). Most of these come from number theory. In all cases, the group axioms should be checked. This is easy for almost all of the examples, an

  • Q : Ordinary Differential Equation or ODE

    What is an Ordinary Differential Equation (ODE)?

  • Q : Problem on Datalog for defining

    The focus is on  the use of Datalog for defining properties  and queries on graphs. (a) Assume that P is some property of graphs  definable in the Datalog. Show that P is preserved beneath extensions  and homomo

  • Q : What is the definition of a group Group

    Group: Let G be a set. When we say that o is a binary operation on G, we mean that o is a function from GxG into G. Informally, o takes pairs of elements of G as input and produces single elements of G as output. Examples are the operations + and x of

  • Q : Law of iterated expectations for

     Prove the law of iterated expectations for continuous random variables. 2. Prove that the bounds in Chebyshev's theorem cannot be improved upon. I.e., provide a distribution that satisfies the bounds exactly for k ≥1, show that it satisfies the bounds exactly, and draw its PDF. T

  • Q : Explain Factorisation by Fermats method

    Factorisation by Fermat's method: This method, dating from 1643, depends on a simple and standard algebraic identity. Fermat's observation is that if we wish to nd two factors of n, it is enough if we can express n as the di fference of two squares.