complex number question

FrostedNipple · 16 Apr 2009 at 15:05

what is z

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in terms of x and y

I make it x^2 + y^2 Am i right?

antijoke · 16 Apr 2009 at 15:07

Ben M · 16 Apr 2009 at 15:07

Don't hotlink

icey_haj · 16 Apr 2009 at 15:08

Flanders · 16 Apr 2009 at 15:11

z.z* = (x+iy)(x-iy)

Assuming you can multiply out, Robert is your Father's brother.

nydryl · 16 Apr 2009 at 15:12

z = x + iy

Bah you edited, thought it seemed a little easy. Yes you are correct.

FrostedNipple · 16 Apr 2009 at 15:13

Flanders said:
z.z* = (x+iy)(x-iy)

Assuming you can multiply out, Robert is your Father's brother.

yeh, when i multiply out i get x^2 +y^2 cause i get

x^2 -xiy + xiy -i^2y^2
x^2 - i^2y^2 i^2 = -1 so
x^2 - -1y^2
x^2 + y^2

Flanders · 16 Apr 2009 at 15:17

FrostedNipple said:
yeh, when i multiply out i get x^2 +y^2 cause i get

x^2 -xiy + xiy -i^2y^2
x^2 - i^2y^2
i^2 = -1 so
x^2 - -1y^2
x^2 + y^2

Spot on

FrostedNipple · 16 Apr 2009 at 15:18

well thats wierd because my father doesn't have a brother