Boolean Algebra | Logic Simplification MCQs

1. The boolean expression $X=B+A\overline{B}+AB$ is equivalent to

  1. A+B
  2. $\overline{A}B$
  3. $\overline{A+B}$
  4. AB

Answer
Answer. a

2. The Boolean expression X = (A + B)(C + D) represents

  1. two ORs ANDed together
  2. two ANDs ORed together
  3. A 4-input AND gate
  4. a 4-input OR gate

Answer
Answer. a

3. Which of the following boolean expressions is ‘NOT TRUE’?

  1. A + 1 = A
  2. $A + \overline{A}=1$
  3. A.A = A
  4. $A.\overline{A}=0$

Answer
Answer. a

4. The complement form of $A(B+C)(\overline{C}+\overline{D})$ is

  1. $A + \overline{B}\,\overline{C}+\overline{D}C=1$
  2. A +BC + CD
  3. A + BC
  4. $\overline{A} + \overline{B}\,\overline{C}+CD$

Answer
Answer. d

5. The simplified form of the boolean expression $\overline{A} + A\overline{B}$ is

  1. A + B
  2. $A +\overline{B}$
  3. $\overline{B} + A$
  4. $\overline{A} + \overline{B}$

Answer
Answer. d

6. If A and B are boolean variables, then what is $(A + B).( A + \overline{B})$ is

  1. B
  2. A
  3. A + B
  4. AB

Answer
Answer. b

7. What is the boolean expression A ⊕ B equivalent to?

  1. $AB+ \overline{A}\,\overline{B}$
  2. $\overline{A}B + A\overline{B}$
  3. B
  4. $\overline{A}$

Answer
Answer. b

8. If x and y are boolean variables, which one of the following is the equivalent of  x ⊕ y ⊕ xy equivalent to?

  1. $x+\overline{y}$
  2. x + y
  3. 0
  4. 1

Answer
Answer. b

9. Which of the following boolean algebra rules is correct?

  1. $A.\overline{A}=1$
  2. A + AB = A + B
  3. $A + \overline{A}B = A + B$
  4. A(A+B) = B

Answer
Answer. c

10. The simplified logic form of a logic function

$Y=\overline{(\overline{A\overline{B}})(\overline{\overline{A}B})}$

  1. A + B
  2. AB
  3. $\overline{A}+\overline{B}$
  4. $\overline{A}B + A\overline{B}$

Answer
Answer. d

11. The boolean expression $Y=AB+ (A+B)(\overline{A}+B)$ may be simplified as

  1. Y = A
  2. $Y = \overline{A}$
  3. Y = B
  4. $Y = \overline{B}$

Answer
Answer. c

12. The reduced form of the boolean expression

$A[B+C(\overline{AB + AC})]$ is

  1. $\overline{A}B$
  2. $A\overline{B}$
  3. AB
  4. $AB+B\overline{C}$

Answer
Answer. c

13. Which one of the following statements is not correct?

  1. $X+\overline{X}Y = X$
  2. $X(\overline{X}+Y) = XY$
  3. $XY + \overline{X}\,\overline{Y} = X$
  4. $ZX + Z\overline{X}Y = ZX + ZY$

Answer
Answer. a

14. In boolean algebra, if $F = (A+B)(\overline{A}+C)$ then

  1. $F = AB + \overline{A}C$
  2. $F = AB + \overline{A}\,\overline{B}$
  3. $F = AC + \overline{A}B$
  4. $F = A\overline{A}+\overline{A}B$

Answer
Answer. c

15. The expression $(X+Y)(X+\overline{Y})(\overline{X}+Y)$ is equivalent to

  1. $\overline{X}\,\overline{Y}$
  2. $\overline{X}Y$
  3. $X\overline{Y}$
  4. XY

Answer
Answer. d