• owenfromcanada@lemmy.world
    link
    fedilink
    English
    arrow-up
    13
    arrow-down
    2
    ·
    15 days ago

    If AB = i and BC = 0, then B would be in the same 2D space as C, but one of them would be “above” the other in 3D space (which doesn’t exist in this context, just as sqrt(-1) doesn’t exist in the traditional sense).

    So this triangle represents a 2D object that is “standing up” on the page.

    • rtxn@lemmy.world
      link
      fedilink
      English
      arrow-up
      7
      ·
      edit-2
      15 days ago

      It makes sense if you represent complex numbers as (a, b) pairs, where a is the real part and b is the imaginary part (just like the popular a + bi representation that can be expanded to a * (1, 0) + b * (0, 1)). AB’s length is (1, 0), AC’s length is (0, 1), and BC’s length will also be a complex number.

      I think.

      • TowardsTheFuture@lemmy.zip
        link
        fedilink
        English
        arrow-up
        1
        ·
        14 days ago

        Yes. Also if you think of i as a 90° rotation (with a length of the scalar coefficient infront of i, in this case 1) . Thus one rotates you outwards away from the 2D plane, and two of those gets you back to the 2D plane, just going the other direction.