# Complex.Multiply Method (Complex, Complex)

.NET Framework (current version)

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Returns the product of two complex numbers.

Namespace:   System.Numerics
Assembly:  System.Numerics (in System.Numerics.dll)

## Syntax

```Public Shared Function Multiply (
left As Complex,
right As Complex
) As Complex
```

#### Parameters

left
Type: System.Numerics.Complex

The first complex number to multiply.

right
Type: System.Numerics.Complex

The second complex number to multiply.

#### Return Value

Type: System.Numerics.Complex

The product of the left and right parameters.

## Remarks

The multiplication of a complex number, a + bi, and a second complex number, c + di, takes the following form:

(ac - bd) + (ad + bc)i

If the multiplication results in an overflow in either the real or imaginary component, the value of that component is either Double.PositiveInfinity or Double.NegativeInfinity.

The Multiply method is implemented for languages that do not support custom operators. Its behavior is identical to multiplication using the multiplication operator.

## Examples

The following example multiples a complex number by each element in an array of complex numbers.

```Imports System.Numerics

Module Example
Public Sub Main()
Dim number1 As New Complex(8.3, 17.5)
Dim numbers() As Complex = { New Complex(1.4, 6.3),
New Complex(-2.7, 1.8),
New Complex(3.1, -2.1) }
For Each number2 In numbers
Console.WriteLine("{0} x {1} = {2}", number1, number2,
Complex.Multiply(number1, number2))
Next
End Sub
End Module
' The example displays the following output:
'       (8.3, 17.5) x (1.4, 6.3) = (-98.63, 76.79)
'       (8.3, 17.5) x (-2.7, 1.8) = (-53.91, -32.31)
'       (8.3, 17.5) x (3.1, -2.1) = (62.48, 36.82)
```

## Version Information

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 4.0
Windows Phone
Available since 8.1