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  • If I remember correctly i = sqrt(-1) is just the definition. If you change the exponent, it's no longer defined as i.

    ((-1)^(1/2))^2 = i^2 = -1

    but
    ((-1)^2)^(1/2) = 1^(1/2) = 1

    Anyway, nice doodles. <3

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  • Aureolen said:
    If I remember correctly i = sqrt(-1) is just the definition. If you change the exponent, it's no longer defined as i.

    ((-1)^(1/2))^2 = i^2 = -1

    but
    ((-1)^2)^(1/2) = 1^(1/2) = 1

    Anyway, nice doodles. <3

    Close. i has 4 possible exponents defined for it, 1 through 4. i^1 = sqrt(-1) as you said, but as math goes, i^2 = -1, i^3 = -i (-1 * sqrt(-1), or -1 * i), and i^4 = 1 (because (-1)^2)

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  • Vaporius said:
    Close. i has 4 possible exponents defined for it, 1 through 4.

    Also, to further nerd because I realized I missed a thing; i can have more than 4 powers, but it's basically "power mod 4", so i^7 = i^3 (7 mod 4 = 3), i^4 technically = 1 because x^0=1 (except where x=0), and i^714 = i^2

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  • Aureolen said:
    If I remember correctly i = sqrt(-1) is just the definition. If you change the exponent, it's no longer defined as i.

    ((-1)^(1/2))^2 = i^2 = -1

    but
    ((-1)^2)^(1/2) = 1^(1/2) = 1

    Anyway, nice doodles. <3

    What the hell

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  • I also want to nerd out since I'm a math major. Not the place I thought I'd put my degree to use but oh well...

    Square root function is discontinuous on the complex plane and we usually use the principal branch, i.e. there's a discontinuation in the negative real axis. Because of this reason some familiar properties aren't true generally, e.g. (xy)^(1/2) != x^(1/2)*y^(1/2) and (x^y)^(1/2) != (x^(1/2))^y.

    The error in the calculation happens when the artist separates (-1)^(2/4) into ((-1)^2)^(1/4).

    Don't tell anyone you learned this from a porn site.

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  • foxxy~ said:
    I also want to nerd out since I'm a math major. Not the place I thought I'd put my degree to use but oh well...

    Square root function is discontinuous on the complex plane and we usually use the principal branch, i.e. there's a discontinuation in the negative real axis. Because of this reason some familiar properties aren't true generally, e.g. (xy)^(1/2) != x^(1/2)*y^(1/2) and (x^y)^(1/2) != (x^(1/2))^y.

    The error in the calculation happens when the artist separates (-1)^(2/4) into ((-1)^2)^(1/4).

    Don't tell anyone you learned this from a porn site.

    Thank you! this is a very good explanation, I won't tell anyone I learned it here

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  • foxxy~ said:
    I also want to nerd out since I'm a math major. Not the place I thought I'd put my degree to use but oh well...

    Square root function is discontinuous on the complex plane and we usually use the principal branch, i.e. there's a discontinuation in the negative real axis. Because of this reason some familiar properties aren't true generally, e.g. (xy)^(1/2) != x^(1/2)*y^(1/2) and (x^y)^(1/2) != (x^(1/2))^y.

    The error in the calculation happens when the artist separates (-1)^(2/4) into ((-1)^2)^(1/4).

    Don't tell anyone you learned this from a porn site.

    I know I'm a few years late to reply to this but I also love this stuff. Great response.

    I just wanted to add on for anyone else who is trying to understand that while 1^(1/4) is equal to 1, 1 actually has 4 potential 4th roots in the complex plain, those being 1,i, -1, and -i, all of which equal 1 when put to the 4th power, so in that sense you can claim any of those numbers are equal to 1 using similar logic:

    let a = any of {1,i,-1,-i}

    a^4 = 1
    (a^4)^(1/4) = 1^(1/4)
    a = 1^(1/4)
    a = 1

    The key detail is really that fractional (non-integer) exponents can represent multiple values in the negative/complex numbers.

    Updated

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