null class उदाहरण वाक्य

Beginning in the middle to late 1800s, these expressions have been used to denote propositions of Boolean Algebra about classes : ( ID ) every class includes itself; ( NC ) every class is such that its intersection ( " product " ) with its own complement is the null class; ( EM ) every class is such that its union ( " sum " ) with its own complement is the universal class.