is duality principle in boolean algebra is true for every expression Let say A = 1 and B = 1
and then A+B = 1
now by using duality(replacing or gate by and gate and 1 by 0) we can say that, A.B = 0
but this is not 0, because 1.1 = 1, so please anyone clear my misunderstanding here, Thank in advance
Negation gives you $\overline{A}=0,\overline{B}=0$, so everything is ok in &quot;and&quot;.