2.5ex I
Syntax

Which of the following are sentences of SL? For this exercise outside parentheses may be dropped and brackets may be used instead of parentheses. Select all correct answers. (Printing is easier at the end: page 4 of 2.5ex I.)

1. ~(AvB)
2. ~AvB
3. ~AvA~
4. ~Av(A&)
5. ~(~A&~B)>(B)
6. ~(~A&~B)>B
7. ~~(~B)=C
8. ~F&(GvS)>~L
9. ~F&[(GvS)>~L]
10. [(Av~S)>D&T]=(S&T)
11. [(Av~S)>(D&T)]=(S&T)]
12. [(Av~S)>(D&T)]=(S&T)
13. ~[[(Av~S)>(D&T)]=(S&T)]
14. ~~~[[(Av~S)>(D&T)]=(S&T)]
15. A>[~~J&U]v[T&S]
16. A>([~~J&U]v[T&S])
17. (L&S)>~[T&(U>J)]
18. (L&S)~>~[T&(U>J)]
19. S
20. (S>&G)v[~J>(P&Q)]