Hint #1: Take home exam #4 is due on April 2nd, and you can get it off the course web page.

Hint#2: To check your work on problem 1: the number of subformulas you need to list = the number of capitol letters + the number of quantifier symbols + the number of connectives (Can you see why this will always be the case?)

Hint#3: To check your work for problem 2, build up the formula from atomics--the main logical operator should be the last thing you add.

Hint #4: To check your work for problem 3, there is only one kind of thing for which you should mark "just a formula"--that's a formula with occurrences of variables that aren't bound by quantifiers. 'Fxy' would be an example. It isn't a sentence, since we don't know whether the x and y are supposed to be universally or existentially quantified. If you will please pretend that my 'A' is upside-down, another example would be '(Ax)(Fx&Hx)&Gx', since the scope of the universal quantifier does not include the G-predicate. The scope of a quantifier always starts immediately to its right and ends as soon as a formula is achieved. Since '(Fx' is not a formula, the scope in our example must extend farther. The scope is '(Fx&Hx)'.

Hint #5: For problem 4, interpret "talk show host" as meaning "talk show host in the U.D." Also, you may find the section in our textbook on A, E, I and O sentences VERY helpful here (especially the bottom half of page 279).

Hint #6: If you give me translations to English on question 5, I will be able to give you better feedback for regrades.

Hint #7: For question 6 (and extra credit), remember that you can use SD rules--only use the SD+ rules where convenient. I can do (a) in 13 lines with SD+, but I can also do it in 18 with just SD. With SD+, I can also do (b) in 4 lines, (c) in 8 lines and the extra credit in 13 lines.

Hint #8: If you need more hints, you can always email me.

Good luck!

Chris