Re:Can 1/3 and 1/3 = 2/6? It seemed so
by saagarjha on Tuesday May 26, 2020 @03:20PM
(#23315354)
That's just lazy, and I haven't ever read a good text use summation where any of the terms would be outright undefined if evaluated.
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You've never seen a textbook present the series form of e^x?
exp(x) = summation(x^n/n!, n=0, inf)
exp(0) = 1 is perfectly valid but the identity above only holds for x=0 only if we define 0^0 = 1. And we do!Fair, infinite series are pretty esoteric. How about derivatives. The power rule:
d/dx x^n = n x^(n-1)
This identity doesn't hold for n = 1 and x = 0 unless 0^0 = 1.Eh maybe not, programmers don't use calculus that often. But surely statistics!
(1 + x)^n = summation((n choose k)x^k, k=0, n)
Take x = 0 and n = 0 (1 + x)^n = (1 + 0)^0 = 1 = 0^0 = x^0 = x^0 + ... + x^n
0^0 is undefined in general but locally we sometimes need to define it.Ok, fair, I think I have seen those. Personally I would prefer noting the special case even when using the fairly standard degenerate case of 0^0=1, but I agree that a lot of people don't.