[Defiant]

I see the "ate summa pi" part. But square root of -1? I thought it doesn't have a square root. The only way you get -1 is 1 x -1.

[grey_whiskers]

sqrt(-1) is the imaginary number i.

Used in electronics and quantum mechanics for two.

[eldoradude]

[Black Agnes]

https://en.wikipedia.org/wiki/Square_root_of_negative_one

[generally]

square root of -1 is i (unless you're an electrical engineer, then it's j) I stands for "imaginary" and it is quite a useful concept in math ∑ is the symbol for "sum" So i 8 sum pi