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Homework · Sentential logic

Derivations

Fresh derivation problems 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 5. Hints and a sample solution are there if you get stuck.

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Every problem has a code, like 2A-0-k3j9a. Anyone who enters the same code gets the same problem, so a tutor can assign one by sending its code. Progress is saved in this browser.

Chapter 5 · SD

Sentential logic derivations

Problems are drawn from a library of classic argument patterns (hypothetical syllogism, dilemma, De Morgan and more), filled in with fresh sentence letters. 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.
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Problem code:—

Or type the whole derivation as text

One line per derivation line. Each | is a scope line. Justifications look like Assumption, A / ⊃I, 1, 3 ⊃E, 2–4 ~I.

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