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Absorption law states that:

Computer Science20241 markMCQ
  • (a)$A \cdot ( A' + B) = A$
  • (b)$A + ( A \cdot B) = A$
  • (c)Both (a) and (b)
  • (d)$A \cdot ( B + C ) = A \cdot B + A \cdot C$

Answer

Answer

AI

Correct option: (b)

Answer: (b) $A + (A \cdot B) = A$ This is the Absorption Law. Option (a) $A \cdot (A' + B)$ expands (by the Distributive Law) to $A \cdot A' + A \cdot B = 0 + AB = AB$, which is not equal to $A$ in general (e.g. $A=1, B=0$ gives $AB=0 \neq A=1$), so (a), and hence (c), are not valid absorption identities.
Boolean Algebra

From ISC 2024 Specimen Computer Science Paper 1, question 1(i).