Sprawdź, czy poniższe formuły są tautologiami:
(1) ~(pVg)-*(~pA~g),
(2) ~(pAg)-*(~pV~g),
(3) (p A (g A ~ r)) —> ((g A ~ p) j r),
(5) ~(pV(ijlr))->((jAr)/~p),
(6) ((plj)Ar)-«(~5-.(~rV~ p)),
(7) ((p A g)/((p V q) —» r)) —. (~ (rA ~ g)V ~ (p = g)),
(9) ((p -.g)A~(~r/~p))^(jV~(rl p)),
(10) (pA~(gsr))-t~(gA(pA (r/g))),
(11) ((p V 9) 1 ~ (r -* a)) -* ((~ a/g) V ~ (r = p)),
(12) ~ ((p -* 9) A (~ r -> (s -* p))) —>(-'■'gV~(p=~(s | r))),
(13) (~ (p = 4) A (~ r -» a)) -* ((p -» (s l r))/ ~ q),
(14) (pi~ (~g ) r)) -> ~ (~ (~pVg) A ((r = s) -*p)),
(15) ~ (p -> ~ (~ (q | r)/(s -* q))) -> ((a = ~p)/(g -» r)).
(16) ((p g)/ ~ (r p)) -t (gV ~ r)
(17) (~ (gA ~p)A(rA(s p)))-* ((r 11) V (~ p I a))
Sprawdź, czy poniższe formuły są tautologiami:
(1) (p = q) -> (p 1 ~ q),
(2) (pAj) -> (~p = ?),
(3) ~ (pVg) -> (p-. (g-*p)),
(4) ((pVj)Ar) -* ((pA?)/r),
(5) ((p A g) X (~ r i a)) -> ~ ((~ p J~ g) = ~ (sV ~ r))
(6) (~ (pAg) A(r -*p)) -» ((pVr)V ~ g),
(7) ((pVg)Xr)^(r V (p X g)),
(8) ((p A g) A (r = a)) -> ((p = g) V (r X a)),
(9) ~ (p V ~ (g i r)) -* (g V (r/p)),
(10) ~ (p /(~ g X~ r)) -* (((r -> ~ g) -* ~ (~ p = r))/(p X~ g))
(11) (~(pV~g)A~(gV r)) -» ~ (p = (gV ~ r)),
(12) ((p V (g r)) As)-* ((g -* s) = (g/r)),
(13) ~ (~ (g -> p) V r) -* ((r/g) X (g A p)),
(14) ((p -> g)A ~(pA r)) -*~ ((g J~ p) V ~ (p/r)),
(15) ~ (~ (g J~ p) A (r V s)) -* ((~ p = (~ g/r)) V (r/(p -* g))),
(16) ~ ((p -* (g -> r)) X ~ (p -> ~ g)) -* ((a A r)/ ~ (s = ~ (p -» (~ g V ~ r)))),