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Homework · Predicate logic · Chapter 10

Derivations (PL)

Fresh quantifier and identity proofs whenever you want them. Choose a difficulty and the rules you want to practise, then build the proof with the same click-to-build checker used in Chapter 10. Hints and a sample solution are there if you get stuck.

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Chapter 10 · PD, PD+, PDE

Predicate logic derivations

Problems come from a library of classic quantifier and identity patterns (universal instantiation, existential syllogism, quantifier negation, swapping quantifiers and more), filled in with fresh predicate letters and names. Every problem comes with a model proof that the checker has already verified.

Difficulty
Kind of problem
Rules to practise
Optional. Leave all off for a mix.
Solve in Identity problems are solved in PDE.
Problem code:—

Or type the whole derivation as text

One line per derivation line. Each | is a scope line. Justifications look like Assumption, A / ∃E, 1 ∀E, 2, 3–6 ∃E, =I. ASCII: (Ax), (Ex), rules UE UI EE EI.

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