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Practice between sessions

Homework

Practice problems that never run out. Each kind of homework has its own page, its own difficulty levels, and instant feedback. Your progress is saved in this browser.

Assigning problems

Every problem has a short code. The same code always gives the same problem, so a tutor can set homework by sending a list of codes, and the student enters them in the "Load a code" box.

SL sentence codes start with T (T2-k3j9a), PL sentence codes with P (P2-k3j9a), SL derivation codes with a level number (2A-0-k3j9a), and PL derivation codes with D (D2A-0-k3j9a).

Sentential and predicate logic

Choose a kind of homework

Chapter 2

Translation (SL)

Symbolize English sentences in SL with a given key: "only if", "unless", "neither … nor" and the rest. Any equivalent answer counts.

Neither Ada nor Ben votes. → ~ (A ∨ B)

Start translating
Chapter 5

Derivations (SL)

Prove arguments and theorems in SD or SD+ with the click-to-build checker. Pick the rules you want to practise; hints and sample solutions included.

{A ⊃ B, B ⊃ C} ⊢ A ⊃ C

Start deriving
Chapter 7

Translation (PL)

Symbolize English in predicate logic: all, some, no, only, relations, names, and identity ("at least two", "exactly one", "everyone except").

Every student likes some teacher. → (∀x)(Sx ⊃ (∃y)(Ty & Lxy))

Start translating
Chapter 10

Derivations (PL)

Prove quantifier and identity arguments in PD, PD+ or PDE with the click-to-build checker: ∀E, ∀I, ∃E, ∃I and =E, with hints and sample solutions.

{(∀x)(Fx ⊃ Gx), (∃x)Fx} ⊢ (∃x)Gx

Start deriving

More kinds of homework, such as truth-trees, can be added here as they become useful.