MHB Ap1.3.51 are complex numbers, show that

AI Thread Summary
The discussion focuses on proving two properties involving complex numbers, specifically that the conjugate of a product and the conjugate of a quotient can be expressed in terms of the conjugates of the individual numbers. Participants clarify that the bar notation represents the complex conjugate. The initial expressions provided are corrected to reflect the proper mathematical relationships. The conversation emphasizes the need for algebraic manipulation to derive the results. Understanding these properties is essential for working with complex numbers in mathematical proofs.
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$\textsf{ If $z$ and $u$ are complex numbers, show that}$
$$\displaystyle\bar{z}u=\bar{z}\bar{u}
\textit{ and }
\displaystyle \left(\frac{z}{u} \right)=\frac{\bar{z}}{\bar{u}}$$ok couldn't find good example on what this is
and I'm not good at 2 page proof systemsso much help is mahalo
 

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I would begin with:

$$u=x_u+y_ui$$

$$z=x_z+y_zi$$

And the see where the algebra leads. :)
 
MarkFL said:
I would begin with:

$$u=x_u+y_ui$$

$$z=x_z+y_zi$$

And the see where the algebra leads. :)

accually what does the bar over mean
 
karush said:
accually what does the bar over mean

That means "the conjugate of." And so, using my prior definitions:

$$\overline{u}=x_u-y_ui$$

$$\overline{z}=x_z-y_zi$$
 
karush said:
$\textsf{ If $z$ and $u$ are complex numbers, show that}$
$$\displaystyle\bar{z}u=\bar{z}\bar{u}
\textit{ and }
\displaystyle \left(\frac{z}{u} \right)=\frac{\bar{z}}{\bar{u}}$$

There are some bars missing. I think that the problem should be asking you to show that $$\bar{z}u=\overline{z\bar{u}}
\text{ and }
\overline{\left(\frac{z}{u} \right)}=\frac{\bar{z}}{\bar{u}}$$
 
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