PS2 grades have been posted. PS3 solutions will be up soon. PS4 will go out tomorrow or on Friday, but will be due November 30th.
As a reminder, the final will be on December the 14th from 7pm to 10pm. It will be closed book, closed notes and will cover all the material in the class (including the three guest lectures at the end of the quarter).
The solutions to problem set 2 have been posted.
A clarification has been sent out for problem set 3; please see the FAQ for ps3.
Problem set 3 has been posted. Due: Thursday Nov. 9 11:59 pm.
(Partial) solutions to problem set 1 have been posted. Solutions to exercise 8 and the extra credit questions will be posted when grading is finished.
In problem 3 of ps2, formal proof is defined as on slide 28 of lecture 7. Therefore you may use the rule of inference universal generalization, as the slide says. Note that there is a difference between UG as a rule and UG as an axiom.
A clarification was made to problem 6 to give you more exact parameters on how you can solve the problem. Also, several things have been added to the PS2 FAQ.
The problem set 2 deadline has been extended to Friday Oct. 27 11:59 at pm. Two small typos have been fixed in problems 1 and 2.
Problem set 2 has been posted. Due: Thursday Oct. 26 11:59 pm.
I have put up a sample proof by induction. Hopefully this will get
you started if you are unsure how to do structural induction, as
opposed to algebraic induction. If you were to submit a proof
resembling this one to the question, I would give you full credit.
Please see: (pdf) (ps)
Never mind
the particularities of proving certain sets of connectives to be
incomplete. (You might find it interesting, though, especially in
light of problem 7.) The important part is the proof structure, not the
context.
Problem set 1, problem 9 misstated the question such that it was impossible to answer it. The corrected version has been posted. Also, problem 11 had a typo in the statement of the substitution theorem.
Problem set 1, problem 10 had an error in it. It should have been referring to alpha and ~alpha'. Please see the updated handout.
Problem set 1 has been posted. Due: Thursday Oct. 12 11:59 pm.
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