Let z be the complex number: x+iy. Then |z|^2=x^2+y^2 according to my book. But according to the general definition of absolute value, |a|=(a^2)^.5. So letting z=a=x+iy. |z|^2=z^2=x^2+2ixy-y^2(adsbygoogle = window.adsbygoogle || []).push({});

This is not equal to x^2+y^2. I'm confused.

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# Confused about the absolute value of a complex number

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