6/26/23 Mation programs correct -understand formal systems -prove - What want -> -proving can't correct chips be proved/computed output or hardware meaningful errors (Intel correct FDIU Bug) Proposition - a statement of fact T P "Toronto is Negation (7) "not p" is F or = the - the thats Canada" of capital = 7 reverses the truth value of proposition one negation P of Conjunction (n)-(p1g),"and" Iisi f p Note: "but" is expresses logically surprise and equivalent is to "and," but Disjunction (v) - (prg)"or"(specifically T "inclusive or") if is por g (or both) are either True none Or))-P,*9birtefact Tin East Note:informally," or" is usually meanta n conditional," logical Conditional()-(p-g)" read Operation Truth 4 Table IPI T - T f F I -isi I proposition of implication, 6) "implies", "p onlyifa Note:Logical implication is "opposite" to 100% certain E door was opens, button pressed causal implication Ju press button, door opens Why ex. Let consider thus Why 2X. (7-T)=T? does p=F, (p - (1 - r q)1(p n(+ T) - T T 1 - f = + ? () is g T, = r) = p F) = F F = - (qur) (T nf) f =T T f) - T? = pistiveinline, are Let Let for for m, m, psg:T, up p falls, is - p contrapositive my is T- T T = = " sunny to also false 49 -up of Converse Contrapositive Inverse of of p > q q p -> is q T I T T 7 F F T I F T ex rain clouds - f Note:words - - is peg Biconditional-(p <5g)" it D is pig is are and p Lequivalent on "necessary" and "sufficient" "sufficient" to conclude clouds (rech"suff" "necessary"for rain (c*r)"nec" Operator Precedence (highestto lowest) 7 negation M conjunction V -> -I disjunction implication bicondition * exclusive or Knights Puzzle: Logic island, knights always tell Knaves lie scare Ipp1, A- "B B- "We is a are A and knight" B opposites" truth, Knaves and Let p Ais B = g lap 2) -p - a) knight = knight is (b) q - 52q2b)2q P - -p