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c# print barcode zebra When And Means Or in Visual C#
When And Means Or Print QRCode In Visual C#.NET Using Barcode creation for VS .NET Control to generate, create QR Code JIS X 0510 image in .NET applications. www.OnBarcode.comScan QR Code ISO/IEC18004 In C#.NET Using Barcode decoder for VS .NET Control to read, scan read, scan image in .NET applications. www.OnBarcode.comIn English and other natural languages, the words and and or are used in a wide variety of situations. In some of these situations they have meanings that seem to contradict their meanings as logical operators. Because of this, you should never be hasty when you attempt to express a realworld notion logically. In the WHERE clause of a query, combining conditions with AND serves to make the number of rows in the result set smaller. However, the English and often corresponds not to the AND of a query s WHERE clause but to the logical operator OR or the set operator UNION. Consider the following English request: Please bring me the latest invoices for customer 45 and customer 17. This doesn t translate into the query predicate custid=45 AND custid=17. Instead, it probably translates into the query predicate custid=45 OR custid=17. On the other hand, this English request doesn t follow the same pattern: Please bring me the latest recipes for ham and eggs. Encoding Bar Code In C#.NET Using Barcode creation for .NET Control to generate, create bar code image in Visual Studio .NET applications. www.OnBarcode.comBarcode Reader In Visual C#.NET Using Barcode recognizer for VS .NET Control to read, scan read, scan image in Visual Studio .NET applications. www.OnBarcode.comInside Microsoft SQL Server 2008: TSQL Querying
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Creating QR Code 2d Barcode In Visual Basic .NET Using Barcode drawer for .NET framework Control to generate, create QR Code image in Visual Studio .NET applications. www.OnBarcode.comDrawing PDF417 2d Barcode In C# Using Barcode generation for .NET Control to generate, create PDF 417 image in .NET framework applications. www.OnBarcode.comIn English, when or doesn t mean and, it still doesn t always mean the same thing as logical or. Logical or means one or the other or possibly both. Sometimes the English word means one or the other but not both, which in a mathematical discussion is distinguished by the name exclusive or. An example of this can be found on many restaurant menus in the phrase includes soup or salad. Print Bar Code In C# Using Barcode generator for Visual Studio .NET Control to generate, create bar code image in .NET applications. www.OnBarcode.comEncode Code 128 In Visual C#.NET Using Barcode drawer for .NET Control to generate, create Code 128 Code Set B image in VS .NET applications. www.OnBarcode.comLogical Equivalence
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Mathematical logic was developed largely as an attempt to justify the way in which mathematicians prove theorems through inference and deduction. One of the most important rules of inference is called modus ponens. Modus ponens is the rule of inference that allows us to infer the truth of one proposition Q from the truth of another proposition P when it s known that P implies Q. An argument using modus ponens might go like this: The law is clear: if you drive faster than 55 miles per hour on this highway, you have broken the law. You were driving faster than 55 miles per hour, therefore you have broken the law. 2
Set Theory and Predicate Logic
Logical inference isn t the focus of this chapter, but we will take a moment to consider propositions that take the form of logical implication. If P, Then Q
Suppose P and Q are valid logical propositions. Then if P, then Q is a valid logical proposition. The proposition if P, then Q is denoted P Q, and its truth value depends on the truth values of P and Q as follows. De nition of P Q
The proposition P Q, read P implies Q or if P, then Q, is true when either P is false or Q is true (or both). The proposition P Q is false when P is true and Q is false. More ( P Q). concisely, (P Q) There is more than one way to express an implication in words, and in mathematical logic, the following expressions are taken to have the precise meanings shown: 1. P unless Q means ( Q) P. 2. P only if Q means P Q. 3. P, if Q means Q P. Note that unlike the logical operators and , the operator values of P Q and Q P are not necessarily the same. is not commutative. The truth

