An automated warehouse security system is designed to trigger an alert if at least two of its three environment sensors—Heat (HHH), Motion (MMM), and Sound (SSS)—are activated at the same time. This logic has been represented by the following Boolean expression, which contains an error:
(H⋅M)+(M⋅S)⋅(H⋅S) (H \cdot M) + (M \cdot S) \cdot (H \cdot S) (H⋅M)+(M⋅S)⋅(H⋅S)Select the correct algebraic expression for this security system.
(H⋅M)⋅(M⋅S)⋅(H⋅S)(H \cdot M) \cdot (M \cdot S) \cdot (H \cdot S)(H⋅M)⋅(M⋅S)⋅(H⋅S)
(H⋅M)+(M⋅S)+(H⋅S)(H \cdot M) + (M \cdot S) + (H \cdot S)(H⋅M)+(M⋅S)+(H⋅S)
(H‾⋅M)+(M⋅S)⋅(H⋅S)(\overline{H} \cdot M) + (M \cdot S) \cdot (H \cdot S)(H⋅M)+(M⋅S)⋅(H⋅S)
(H⋅M)⋅(M⋅S)+(H⋅S)(H \cdot M) \cdot (M \cdot S) + (H \cdot S)(H⋅M)⋅(M⋅S)+(H⋅S)
30 exam-style questions on AQA GCSE Computer Science Boolean logic. Each one has a worked solution and a mark scheme showing where the marks go.