- #1

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**Complex Numbers**

Hello,

Why when dealing with complex numbers, as with multiplication, we use the complex conjugate operator?

Regards

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- Thread starter EngWiPy
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- #1

- 1,367

- 61

Hello,

Why when dealing with complex numbers, as with multiplication, we use the complex conjugate operator?

Regards

Last edited:

- #2

- 5,439

- 9

Compare what happens in the following

[tex]\frac{{a + ib}}{{c + id}}*\frac{{c - id}}{{c - id}}[/tex]

with

[tex]\frac{{a + ib}}{{c + id}}*\frac{{c + id}}{{c + id}}[/tex]

- #3

- 1,367

- 61

Compare what happens in the following

[tex]\frac{{a + ib}}{{c + id}}*\frac{{c - id}}{{c - id}}[/tex]

with

[tex]\frac{{a + ib}}{{c + id}}*\frac{{c + id}}{{c + id}}[/tex]

I didn't get it. I mean, in telecommunication systems, when we deal with baseband signals, we deal with complex numbers, and all the time we use the complex conjugate operator, but I don't understand why and what it is mean physically.

- #4

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- 9

Which one contained the conjugate and which one leads to a single complex number result?

If you apply a formula in real analysis say 27*3 you want the simple answer 81, not something more difficult than you started with such as

[tex]{\left( {\sqrt 9 } \right)^2}*{\left( {\sqrt 9 } \right)^2}[/tex]

The same is true of complex numbers.

What does simple multiplication by a conjugate yield by the way ( a real number)?

- #5

HallsofIvy

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