Simplify the following expression: (A + B + 1) . (A' +B' + 1) . (A + B + C) .…
2021
Simplify the following expression:
(A + B + 1) . (A' +B' + 1) . (A + B + C) . (A' +B' + C')
- A.
1
- B.
[(A + C)B'] + [(B + C)A'] + [(A + B)C']
- C.
[(A+C)B'] + [(B+C)A']
- D.
A+B+C
Attempted by 100 students.
Show answer & explanation
Correct answer: B
Step 1: Simplify terms involving the constant '1'
In Boolean algebra, the Identity Law states that X + 1 = 1.
The first term (A + B + 1) simplifies to 1.
The second term (A' + B' + 1) simplifies to 1.
The expression now becomes: 1 \cdot 1 \cdot (A + B + C) \cdot (A' + B' + C')
Since 1 \cdot X = X, we are left with:
(A + B + C) \cdot (A' + B' + C')
Step 2: Expand the remaining terms
We distribute (A + B + C) over (A' + B' + C'): (A \cdot A') + (A \cdot B') + (A \cdot C') + (B \cdot A') + (B \cdot B') + (B \cdot C') + (C \cdot A') + (C \cdot B') + (C \cdot C')
Step 3: Apply the Complement Law
The Complement Law states that X \cdot X' = 0.
A \cdot A' = 0
B \cdot B' = 0
C \cdot C' = 0
The expression simplifies to:
AB' + AC' + BA' + BC' + CA' + CB'
Step 4: Group and Factor
Group the terms to match the requested format:
(AB' + CB') + (BA' + CA') + (AC' + BC')
Factor out the common variables:
B'(A + C) + A'(B + C) + C'(A + B)
Final Answer
The simplified expression is [(A + C)B'] + [(B + C)A'] + [(A + B)C'], which corresponds to Option 2.