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    I am really struggling on how to work out a complex number after being given the argument and modulus. Is there a specific method or does it just require some trial and error and educated guessing?
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    (Original post by Crozzer24)
    I am really struggling on how to work out a complex number after being given the argument and modulus. Is there a specific method or does it just require some trial and error and educated guessing?
    sines and cosines
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    (Original post by Crozzer24)
    I am really struggling on how to work out a complex number after being given the argument and modulus. Is there a specific method or does it just require some trial and error and educated guessing?
    Uhm, if you're given the modulus and argument, then you just compute:

    z = |z| (\cos \theta + i \sin \theta), e.g: modulus = 1, argument = pi/6, then:

    \displaystyle z  = 1(\cos \frac{\pi}{6} + i \sin \frac{\pi}{6}) = \frac{\sqrt{3}}{2} + i \frac{1}{2}.
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    As above. If you do AS physics, it's much like your study or resolving vectors in 2 dimensions. Finding the vertical component (imaginary part) and horizontal component (real part) given the magnitude and angle of inclination.
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    (Original post by Asurat)
    As above. If you do AS physics, it's much like your study or resolving vectors in 2 dimensions. Finding the vertical component (imaginary part) and horizontal component (real part) given the magnitude and angle of inclination.
    AS Physics? M1 has that.
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    (Original post by Zacken)
    Uhm, if you're given the modulus and argument, then you just compute:

    z = |z| (\cos \theta + i \sin \theta), e.g: modulus = 1, argument = pi/6, then:

    \displaystyle z  = 1(\cos \frac{\pi}{6} + i \sin \frac{\pi}{6}) = \frac{\sqrt{3}}{2} + i \frac{1}{2}.
    (Original post by Asurat)
    As above. If you do AS physics, it's much like your study or resolving vectors in 2 dimensions. Finding the vertical component (imaginary part) and horizontal component (real part) given the magnitude and angle of inclination.
    (Original post by TeeEm)
    sines and cosines
    Haha thank you! Seems so simple now you know how to do it
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    (Original post by Crozzer24)
    Haha thank you! Seems so simple now you know how to do it
    Glad we helped! Have you understood it completely? What if I asked you to convert: modulus = 2, argument = pi/3 into z = a + ib, how would you do that?
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    (Original post by Zacken)
    AS Physics? M1 has that.
    That too ^^ My first thought was AS physics as at my school the mechanics modules are taught at A2.
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    (Original post by Zacken)
    Glad we helped! Have you understood it completely? What if I asked you to convert: modulus = 2, argument = pi/3 into z = a + ib, how would you do that?
    Z= 1 + ((root3)/2) j hard to type square roots haha
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    (Original post by Crozzer24)
    Z= 1 + ((root3)/2) j hard to type square roots haha
    Almost! Remember, you're doing 2(0.5 + sqrt(3)/2 i) = 1 + sqrt(3)i, there shouldn't be that sqrt(3)/2.
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    (Original post by Zacken)
    Almost! Remember, you're doing 2(0.5 + sqrt(3)/2 i) = 1 + sqrt(3)i, there shouldn't be that sqrt(3)/2.
    Oh god of course! Thank you for the help
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    (Original post by Crozzer24)
    Oh god of course! Thank you for the help
    No problemo! Glad you caught on.
 
 
 
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