Yeah, my son only knows about imaginary numbers as far as the veritasium "epic math dual" video. As far as I can tell he inferred that |i+1| needs the Pythagor

Yeah, my son only knows about imaginary numbers as far as the veritasium "epic math dual" video. As far as I can tell he inferred that |i+1| needs the Pythagorean theorem and that i and 1 are legs of the right triangle. I don't think anyone ever suggested that "absolute value" is "length". I asked him what |2i+2| would be an his answer of "square root of 8" suggests that he doesn't have it memorized as an answer because if it was he'd have said "2 square root two" or something similar. I also asked if he'd seen a video about this and he said no. I think he just figured it out himself. Which is mildly spooky.