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    Name:  IMG_0461.jpg
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Size:  500.9 KB how do you do the 1ii) this thing has always confused me Name:  IMG_0462.jpg
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Size:  492.1 KB the screens are a bit upside down thanks for the help in advance,
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    (Original post by Ganhad)
    Name:  IMG_0461.jpg
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Size:  500.9 KB how do you do the 1ii) this thing has always confused me Name:  IMG_0462.jpg
Views: 71
Size:  492.1 KB the screens are a bit upside down thanks for the help in advance,
    Sorry, those images hurt my eyes :confused:

    Is the 2nd pic supposed to be your working for the problem?

    If you've found the modulus r and the argument \theta so you have written z=re^{i\theta}, then the principal cube root is r^{1/3}e^{i\theta/3} for example.
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    After you have the principle cubed root, note that theta=theta+2pi=theta+4pi
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    (Original post by aznkid66)
    After you have the principle cubed root, note that theta=theta+2pi=theta+4pi
    I know what you mean, but that's not literally true is it?
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    Well, I don't see how it's not. They represent the same point on the unit circle ._.

    EDIT: But yes, I guess it would be better to say that they are equivalent angles rather than equal values.
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    (Original post by aznkid66)
    Well, I don't see how it's not. They represent the same point on the unit circle ._.

    EDIT: But yes, I guess it would be better to say that they are equivalent angles rather than equal values.
    Yes, the point is that exp(i x angle2) = exp(i x angle1) etc, not that the angles are equal
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    But the angles are equal; theta radians is always equal to theta+2pi radians, even outside of Euler form ._.
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    (Original post by aznkid66)
    But theta radians is always equal to theta+2pi radians, even outside of Euler form ._.
    i think we're arguing semantics now

    Rotation through one angle produces the same effect as rotation through another angle. I personally would not write angle1 = angle2 in this case.

    I appreciate you understand what is going on, but an unsympathetic examiner might not, so I would err on the side of caution and write something like:

    e^{i\theta} = e^{i(\theta + 2n\pi)}

    to be explicit about what I'm arguing in an exam.
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    (Original post by davros)
    i think we're arguing semantics now

    Rotation through one angle produces the same effect as rotation through another angle. I personally would not write angle1 = angle2 in this case.

    I appreciate you understand what is going on, but an unsympathetic examiner might not, so I would err on the side of caution and write something like:

    e^{i\theta} = e^{i(\theta + 2n\pi)}

    to be explicit about what I'm arguing in an exam.
    so would one of the answers for question 1ii) e^(7/4pi)?
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    (Original post by Ganhad)
    so would one of the answers for question 1ii) e^(7/4pi)?
    I haven't worked through the question in detail, but isn't 7pi/4 the argument of the original number and not one of the cube roots?
 
 
 
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