Sum-Of-Products (SOP) Form

A logic expression consisting of product (AND) terms that are summed (ORed) is said to be of the sum-of products (SOP) form.

Basically, look at the truth table and look at everywhere where the result is true (1). Then do the sum of products where those things are true.

Product of Sums is very similar idea, but when the output is 0.

title: Standard/Canonical SOP
A standard SOP expression is one in which all the variables in the domain appear in each product term in the expression. 
Ex: $\overline{A}BCD + AB\overline{C}D + ABC\overline{D}$ is a standard SOP expression.

Converting Product Terms to Standard SOP

Step 1. Multiply each nonstandard product term by a term made up of the sum of a missing variable and its complement. Step 2. Repeat Step 1 until all resulting product terms contain all variables in the domain in either complemented or uncomplemented form. Example

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