#### Test 2, Quizzes 4-6, Homework Assignments 4-5

Quiz 4, available at
noon 02/13/14, covers 4.1-4.2 and NTMs of chapter 3, due midnight 02/16/14

Practice problems

3^{rd} edition: 4.1-4.14, 4.20, 4.24-4.25, 4.30

2^{nd} edition: 4.1-4.13, 4.18, 4.22-4.23, 4.28

Homework 4 due midnight 02/19/14

Textbook problems

3^{rd} edition: 3.16 a-d, 4.8, 4.17, 4.29, 3.18 (extra credit)

2^{nd} edition: 3.16, 4.7, 4.16, 4.27, 3.18 (extra credit)

Quiz 5, available at noon 02/20/14, covers 5.1-5.3,
due midnight 02/23/14, Solutions of Quiz 5
problems

Practice problems

3^{rd} edition: 5.1-5.7, 5.9-5.11, 5.22-5.23, 5.28

2^{nd} edition: 5.1-5.7, 5.9-5.11, 5.22-5.23, 5.28

Homework 5 due midnight 02/26/14

Textbook problems

3^{rd} edition: 5.16-5.17, 5.26, 5.32, 5.33 (extra credit)

2^{nd} edition: 5.16-5.17, 5.26, 5.32, 5.34 (extra credit)

#### Quiz 6, available at noon 02/20/14, covers 6.1-6.3, due
midnight 03/02/14

Practice problems

3^{rd} edition: 6.2-6.5, 6.8-6.10, 6.12-6.13

2^{nd} edition: 6.2-6.5, 6.8-6.10, 6.12-6.13

Test 2, available from noon 02/27/14, covers
NTMs of chapter 3, 4.1-4.2, 5.1-5.3, 6.1-6.3, due midnight 03/02/14

Practice problems

3^{rd} edition: 4.16, 4.26, 5.13-5.15, 5.21, 5.29-5.30, 6.2-6.5,
6.8-6.10, 6.12-6.13

2^{nd} edition: 4.15, 4.24, 5.13-5.15, 5.21, 5.29-5.30, 6.2-6.5,
6.8-6.10, 6.12-6.13

Theorems for Test 2 (you need to be familiar with all
theorems listed below and with their proofs):

1. Equivalence of NTMs and TMs, Theorem 3.16

2. Undecidability of the acceptance problem for TMs, Theorem 4.11

3. Decidability of the acceptance problem for LBAs, Theorem 5.9

4. Undecidability of the emptiness problem for LBAs, Theorem 5.10

5. Undecidability of the all strings problem for CFGs, Theorem 5.13

6. PCP, Theorem 5.15

7. The problem of equality of TM-recognizable languages, Theorem 5.30

8. Recursion theorem, Theorem 6.3