Logic circuits

What is the simplified result of the expression A + A·B?

  1. AA
  2. BB
  3. CA·B
Show answer and explanation

Answer: A. A

A + A·B = A·(1 + B) = A·1 = A (the absorption law). If A is 1 the whole expression is 1, and if A is 0 then A·B is also 0, so the whole is 0. The result equals A regardless of B.

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