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Conjugate of either sin or cos

  1. Sep 24, 2006 #1
    okay, so this particular equation involves me writing conjugate of either sin or cos, but hows that possible considering they both are real in the given problem?

    maybe i should convert sin and cos into their exponential form first?

    but then wt would be the conjugate of this expression-----> e^2j +e^(-2j)?
  2. jcsd
  3. Sep 24, 2006 #2
    If you have to take the complex conjugate of a real quantity, say [itex]z[/itex], then [itex]z[/itex] is its own complex conjugate, i.e. [itex]z=z^{\ast}[/itex]. This follows from the fact that the real part of a complex number and the real part of its conjugate are always the same by definition:

    z = x + iy
    z^{\ast} = x - iy

    where [itex]x\,,y[/itex] are real.
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