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Complex number proof

  1. Mar 16, 2007 #1

    could someone please help me out with proving the following:
    |z1|^2/|z2|^2 = |z1/z2|^2

    ...with complex numbers

    sorry im not familiar with the coding here yet so i can't write that properly
  2. jcsd
  3. Mar 16, 2007 #2


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    How is division defined on the complex numbers?
    Use that to get the result, alternatively use polar representation of the numbers.
  4. Mar 16, 2007 #3
    simply define z1 = a + jb and z2 = l + jm;
    LHS - take modulus of each and keep it aside...i.e., a^2 + b^2 is modulus;
    RHS - Rationalise the den. & num., i.e, z1/z2 = (a + jb)*(l - jm)/(l2 + m2);
    seperate out the real & imaginary parts...u'll find LHS = RHS...
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