Wanted to share this, since 90% of the activities I make rely HEAVILY on this weird little property, it's algebraically sound as well. Really cool thing is you can also derive and integrate by treating y/x as a variable, without breaking math. Just don't expect anything to work in a way that makes sense initially. Anyway, here I show that utilizing (1+ui) in place of (x+yi) results in a surface that is 90% identical (a couple curves move or disappear, but everything else is identical). I did this with the complex root of an imaginary number to keep things simple, I also derove a quantity equivalent to that (based off what my zeros would have to be for the real and imaginary portion to go to zero, because this is in reality just pi/2 to pi, and I just want to rotate things properly). I included both f(x+yi) and f(1+ui) for both equations to show how (incredibly well) this works. This isn't substitution though, if you were to actually solve for "u" (not always possible without doing crazy amounts of geometry and algebra), it will give you the (x,y) curve. I call it an (x,y) curve because it represents the angle/hyperbole/whateveritmaybe as it changes. This I did not show, because it's difficult, but works perfectly with the imaginary root of either a complex or imaginary number.
