Stereographic Projection of z and 1/z Reflections in Reimann Sphere

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Show that the stereographic projections of the points z and 1/\overline{z} are reflections of each other in teh equatorial plane of the Reimann sphere

ok so let z = x + iy
then \frac{1}{\overline{z}} = \frac{x - iy}{x^2 + y^2}
so the magnitude of \frac{1}{\overline{z}} is \frac{1}{x^2 + y^2}

the stereogrpahic projection of z is
x_{1} = \frac{2x}{x^2 + y^2 +1}
y_{1} = \frac{2y}{x^2 + y^2 +1}
z_{1} = \frac{x^2 + y^2 -1}{x^2 + y^2 +1}

for 1/ z bar is
x_{2} = \frac{2x(x^2 + y^2)^2}{1 + (x^2 + y^2)^2}
y_{2} = \frac{2y(x^2 + y^2)^2}{1 + (x^2 + y^2)^2}
z_{2} = \frac{1-(x^2 + y^2)^2}{1 + (x^2 + y^2)^2}
i fail to see how these are reflections of each other, then shouldn't the x1 = - x2?? and so on??

please help!
 
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stunner5000pt said:
so the magnitude of \frac{1}{\overline{z}} is \frac{1}{x^2 + y^2}
You sure about that?
 
assyrian_77 said:
You sure about that?
perhaps I am missing something here??
 
stunner5000pt said:
perhaps I am missing something here??
Well, the magnitude of a complex number z=x\pm iy is |z|=\sqrt{x^2+y^2}, but you probably know this already. You have the complex number

\frac{1}{\overline{z}}=\frac{x-iy}{x^2+y^2}=\frac{x}{x^2+y^2}-i\frac{y}{x^2+y^2}

I get a different magnitude than yours.
 
ys i got what u got ( i made a sign error)

so the magnitude would be...
\sqrt{\left(\frac{x}{x^2 + y^2}\right)^2 +\left(\frac{y}{x^2 + y^2}\right)^2} = \sqrt{\frac{1}{x^2 + y^2}}

the projection is then

x_{2} = \frac{2x(x^2 + y^2)}{1 + (x^2 + y^2)}

right?
i know sily math errors everywhere!
 
is what i did in the above post correct now??
 
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