Question

Which of the following Boolean equation is/are incorrect? Write the correct forms of the incorrect ones :

(a)  A + A’ =1

(b)  A + 0 = A

(c) A . 1 = A

(d)  AA’=1

(e)  A+ AB = A 

(f) A(A+B)’ = A 

(g)  (A+B)’ = A’ + B

 (h)  (AB)’=A’B’

(i)  A + 1 =1

(j)  A + A =A 

(k)  A + A’B = A +B

(l)  X +YZ = (X + Y)(X + A)

Answer 1

(a) Correct

(b) Correct

(c) Correct

(d) Incorrect. Correct form is A . A’ = 0

(e) Correct

(f) Correct

(g) Incorrect. Correct form is (A + B)’ = A’B’

(h) Incorrect. Correct form is (AB), = A’ + B

(i) Correct

(j) Correct

(k) Correct

(l) Incorrect. Correct form is X + YZ = (X + Y)(X + Z)