6.4.x. Exercise questions

1. Each of a, b, and c gives a structure in one of the two sorts of presentation described in this section—by a diagram or by tables. Present each of them in the other way.
  a.
  b.
τ
0T
1T
2F
 
τ
0F
1F
2T
 
R0 1 2 
0T T T 
1F T F 
2F T T 
  c.
τ
0T
1T
2F
 
τ
0F
1T
2T
 
τ
0T
1F
2T
 
R0 1 2 
0F T F 
1T F F 
2F T F 
2. Calculate a truth value for each of the following sentences on the structure used as the chief example in this section (see, for example, Figure 6.4.2-7):
  a. (Fa ∨ Gb) → Rab
  b. R(fca)(fac)
  c. fab = fba
3. Use derivations to check each of the claims below; if a claim of entailment fails, use either tables or a diagram to present a structure that divides an open gap.
  a. a = a → Fa ⇒ Fa
  b. ¬ (Fa ∧ Fb) ⇒ ¬ Fa → ¬ Fb
  c. a = b ∨ b = a ⇒ a = b ∧ b = a
  d. Fa → a = b, ga = b, Ra(ga) → Fa, F(ga) ⇒ Raa → R(ga)(ga)
  e. a = b → Rac, ¬ a = b → Rbc ⇒ Rbc

For more exercises, use the exercise machine.

Glen Helman 28 Aug 2008