Logical Conjunction and Disjunction

 Conjunction

 You can use a logical conjunction to combine two or more Boolean expressions. To do this, use the Where statement to create the expression as you see fit and add an And conjunction to it. Here is an expample:
```Imports System.Linq
Imports System.Collections.Generic

Module Exercise
Public Function Main() As Integer
Dim Numbers = New List(Of Integer)

Dim Number = From N
In Numbers
Where N Mod 2 = 0 And N <= 100
Select N

For Each member In Number
Console.WriteLine(member)
Next

Console.WriteLine()
Return 0
End Function
End Module```

This would produce:

Once again, remember that the use of parentheses makes it easier to read the code and better understand it:

```Imports System.Linq
Imports System.Collections.Generic

Module Exercise
Public Function Main() As Integer
Dim Numbers = New List(Of Integer)

Dim Number = From N
In Numbers
Where (N Mod 2 = 0) And (N <= 100)
Select N

For Each member In Number
Console.WriteLine(member)
Next

Console.WriteLine()
Return 0
End Function
End Module```

Or better yet:

```Imports System.Linq
Imports System.Collections.Generic

Module Exercise
Public Function Main() As Integer
Dim Numbers = New List(Of Integer)

Dim Number = From N
In Numbers
Where ((N Mod 2) = 0) And (N <= 100)
Select N

For Each member In Number
Console.WriteLine(member)
Next

Console.WriteLine()
Return 0
End Function
End Module```

To negate a conjunction, precede it with a ! operator. Remember that a conjunction is made of two parts. Therefore, if you want to negate only the first part, precede it with !. If you want to negate the whole conjunction, put the conjunction in parentheses but precede it with ! (outside the parentheses).

 Disjunction

When creating a LINQ statement, you can use a logical disjunction, which is represented by the Or operator. Here is an example:

```Imports System.Linq
Imports System.Collections.Generic

Module Exercise
Public Function Main() As Integer
Dim Numbers = New List(Of Integer)

Dim Number = From N
In Numbers
Where ((N Mod 2) = 0) Or (N Mod 5 = 0)
Select N

For Each member In Number
Console.WriteLine(member)
Next

Console.WriteLine()
Return 0
End Function
End Module```

This would produce:

```12
45
38
5
128
525
2448
632

Press any key to continue . . .```