fra0103 Summary of Complex Numbers for Electronics Technology

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Multiplying Complex Numbers
Polar Form

 This is the  formal expression for multiplying complex numbers in polar form: aÐA x bÐB = abÐ(A + B)

The procedure for multiplying two complex numbers in polar form is fairly straightforward.

Here are two different complex numbers:

2Ð20° and 4Ð15°

Here is how to show that the two values are to be multiplied:

2Ð20° x 4Ð15°

or

(2Ð20°)(4Ð15°)

To multiply these numbers, first multiply the length components
(2
Ð20°)(4Ð150°):

2 x 4 = 8

(2
Ð20°)(4Ð15°)

20° + 15° = 35°

Putting together the length and angular components:

8Ð35°

So the overall result is:

(2Ð20°)(4Ð15°) = 8Ð35°

Learn From More Examples

1.          3Ð12° x 7Ð-54° = 21Ð-42°
2.          10
Ð-4° x 8Ð-45° = 80Ð-49°
3.          8
Ð82° x 9Ð13° = 72Ð95°
4.          8
Ð-56° x 10Ð-21° = 80Ð-77°
5.          10
Ð27° x 7Ð-64° = 70Ð-37°
6.          6
Ð-72° x 6Ð-32° = 36Ð-104°
7.          7
Ð88° x 7Ð-14° = 49Ð74°
8.          4
Ð87° x 1Ð-47° = 4Ð40°
9.          8
Ð58° x 5Ð-23° = 40Ð35°
10.          7
Ð-22° x 1Ð-89° = 7Ð-111°