5.4 Standard Sum-of-Products Representation

• Logic expressions in the sum-of-products form are represented using two levels of operations as a set of product (AND) terms, each comprising one or more variables in their true forms (for example, A) or complement forms (e.g., A), combined using the OR function

• We can write a sum-of-products expression from a truth table representation by first writing a product term for each row in the truth table with a 1 in its output column, and then summing these product terms. Each product term comprises an AND function of all the input variables. A variable will appear in its true or complement form in a product term corresponding to a given row in the truth table depending on whether it appears as a 1 or a 0 in that row