Exam-style question
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Use Boolean algebra to simplify F = (A + B)(A + NOT B). Show how the expression changes between each line.
Model answer
What a good answer should say
- F = (A + B)(A + NOT B) = A + B(NOT B) = A + 0 = A.
- Therefore, F = A.
Explanation
Why this works
Apply the distributive identity (A + B)(A + C) = A + BC, with C equal to NOT B. Since B AND NOT B = 0 by the complement law, the expression becomes A + 0.
The identity law for OR then gives A.
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