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Simplify the following expression, using Boolean laws:
Simplify the following expression, using Boolean laws:
$( X + Z ) . ( X.Y + Y.Z' ) + X.Z + Y$
Answer
Answer
AI$(X+Z).(X.Y+Y.Z') + X.Z + Y$
$X.Y+Y.Z' = Y.(X+Z')$ (Distributive law - factor out Y)
$(X+Z).(X.Y+Y.Z') = (X+Z).Y.(X+Z') = Y.(X+Z).(X+Z')$
$(X+Z).(X+Z') = X+Z.Z' = X+0 = X$ (Distributive law, then Complement law $Z.Z'=0$, then Identity law)
So $(X+Z).(X.Y+Y.Z') = Y.X = XY$
Expression becomes: $XY + XZ + Y$
$XY+Y = Y$ (Absorption law), so $XY+XZ+Y = (XY+Y)+XZ = Y+XZ$
Final simplified expression (verified with the boolean tool): $F = Y + XZ$
From ISC 2019 Computer Science Paper 1, question 6(c).