1) ((a v ¬b) ↔ b)*(¬a v b) = (¬(a v ¬b) v b)*(¬b v a v ¬b)*(¬a v b) = (¬a * b v b)*(a v ¬b)*(¬a v b) = b*(a v ¬b)*(¬a v b) = a*b*(¬a v b) = b*a*b = a*b
a*b=1 при a=1, b=1; во всех остальных случаях a*b=0
2) ¬(a*b) ↔ (¬a v b) = (a*b v ¬a v b)*(¬(¬a v b) v ¬(a*b)) = (b v ¬a)*(a*¬b v ¬a v ¬b) = (b v ¬a)*(¬a v ¬b) = ¬a v (b * ¬b) = ¬a
a=0; b=1; => ¬0 = 1