Homework 4 -- due Wednesday April 1

Written questions

1. [15 points] Answer Question 7.12 of the textbook
2. [10 points] Answer Question 8.3 of the textbook
3. [10 points] Answer Question 8.8 of the textbook
4. [10 points] Answer Question 9.4 of the textbook
5. [15 points] Answer Question 9.18 of the textbook
6. [20 points] Answer Question 9.19 of the textbook
7. [10 points] This is only for Graduate Students (an old WPE question). Undergraduate students do not need to answer this question, they will get credit for it without having to do any work. Undergraduates are welcome to answer this question for extra credit.
   Prove by resolution that the following set of expressions is unsatisfiable. Upper case arguments are constants, lower case arguments are variables:
   1. forall x Expensive(x) -> Prestigious(x)
   2. forall x Prestigious(x) -> Big(x)
   3. forall x Prestigious(x) -> Nicer(x,Garden)
   4. forall x forall y Big(x) -> not Nicer(x,y)
   5. Expensive(Myhouse)
   6. Big(Myhouse) -> Nicer(TomHouse,Myhouse)