logic - If not (a and not b) and if (not a and b) -


can explain why these 2 statements aren't equal?

if not(a , not b):  // stuff   if (not , b): // stuff

i tried make program more understandable changing first statement second doesn't work. don't totally understand why.

you should de morgan's thereom, half of (a):

not(p , q) -> not(p) or not(q)

in terms of how applies situation, replace p a , q not(b):

not(a , not b) -> not(a) or not(not(b))                  -> not(a) or b

(a) other half is:

not(p or q) -> not(p) , not(q)

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