Optional problems are exactly what the words say: you do
not have to hand them in and they will not be taken into account
in computing your basic grade for the class. However: you should
try them and then check out the solutions if your interest in the
class is more than casual; and any solutions you might hand in
will play a role in possibly earning an A+ for the class.
HW #6, due Thursday, Feb. 28, in section: x4B.1, x4B.7,
x4B.8, x4B.9, x4B.10, x4B.11. Solutions
HW #5, due Monday, Feb. 25, in class: x4A.1, x4A.2, x4A.3, x4B.2,
x4B.3, x4B.4, x4B.5, x4B.6. Solutions
HW #4, due Thursday, Feb. 15:
For the first two of these problems you will need to use some of
the theorems in Section 2C whose proofs we have omitted. We
indicate in each case which theorems you may use.
x2D.1 (you may use the Soundness Theorem 2C.2), x2D.2 (you may
use the Transitivity Corollary 2C.4), x3A.1, x3A.2, x3A.3,
x3A.6, x3A.7, x3A.8.
Optional. x2C.2. (The solution of this problem depends on
the methods used in the proofs of the basic theorems 2C.2, 2C.4
and 2C.5 as well as an understanding of how the recursive machine
works, especially Lemma 2C.1. Aside from its proof, however, it
is worth thinking about what it means, which is the main
reason it is included here.)
Solutions (03/3: corrected bad typo
in the solution of x3A.1 noticed by Matt Knauff.)
HW #3, due Thursday, Jan. 31: x2A.1, x2A.2, x2A.6, x2A.7, x2A.8, x2A.9,
x2A.10, x2B.1, x2B.3.
Optional. x2A.3.
Solutions
HW #2, due Thursday, Jan. 24:
x1A.13, x1C.2, x1C.6, x1C.9, x1C.10, x1C.11, x1C.12, x1C.13.
Optional. x1A.14, x1B.25, x1C.8.
Solutions
HW #1, due Thursday, Jan. 17: x1A.11, x1A.12, x1B.2,
x1B.3, x1B.5, x1B.8, x1B.10, x1B.17, x1B.20. Solutions
HW #0, due Thursday, Jan. 10: x1A.5, x1A.6, x1A.7, x1A.8.
(Not collected.) Solutions.