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0^0

askamathematician.com

11–20 of 256 posts

Re: 0^0

#11
Students: Let's come up with some crazy proofs based on our individual levels of understanding.

Teachers: Let's do it by the book and come up (somehow) with conflicting answers.

Mathematicians: Yeah, sorry guys. We made it all up.

Pretty much captures most mathematicians I know.

Re: 0^0

#12
post #7

That's a rather long text to say "it's an arbitrary -- and conveniently chosen -- definition of a special case of the power function similar to how 1 is not prime". I also think the presentation was chosen poorly: lots of wrong information before the correct approach is presented. Wikipedia is probably a better source here: https://en.wikipedia.org/wiki/0%5E0#Zero_to_the_power_of_zer...

In no way was wikipedia better, it was confusing and basically incomprehensible unless you already understood the material.

His presentation was much better because it leads you to the answer instead of dropping it on you from the sky. (The difference between learning by rote vs learning by understanding.)

Re: 0^0

#13

This is ridiculous. Doesn't this seem counter-intuitive for it to be anything else besides 0 or undefined?

Not really - the explanation from the "mathematician" perspective gives some of the rationale, and it makes perfect sense & in line with intuition.

Defining 0^0 as anything but 1 is weird since x^0 is 1 given the other definitions we have adopted, i.e. x^n = x * x * ... * x (n times) for positive integers, (x^n)^(-1) being defined as the unique number such that x^n * (x^n)^(-1) = 1, (x^n)^(-1) * x^n = 1 for non-zero numbers x, and the simple result that (x^n)^(-1) = (x^(-1))^n from proof by induction & the uniqueness condition of the multiplicative inverse, we then get the natural formula that 1 = x^n * x^(-n) = x^(n - n) = x^0 for non-zero numbers. Defining 0^0 = 0 or undefined doesn't agree with the formula given for all non-zero real numbers, and goes against the limit of x^x as x approaches 0 (as detailed in the article), making x^x a discontinuous function at x = 0 if it is defined as another value.

Re: 0^0

#14

Missing Q and A: But if mathematicians insist it is 1, why do high school teachers act like they know more than the mathematicians do? A: They don't. The statement that mathematicians uniformly say it is 1 is simply false. My high school teacher had a PhD in math, I think it's fair to say she was a mathematician. And yes, she said it was undefined.

I think it might be better to say it's indeterminant.

Re: 0^0

#15

Students: Let's come up with some crazy proofs based on our individual levels of understanding. Teachers: Let's do it by the book and come up (somehow) with conflicting answers. Mathematicians: Yeah, sorry guys. We made it all up. Pretty much captures most mathematicians I know.

Definitions in mathematics are used to make the language describing abstract concepts elegant, as explained in the entry.

However, definitions aren't chosen all willy-nilly - there are good arguments why definitions are adopted, as should have been seen in the article.

Re: 0^0

#16
It also plays nice with the convention of 0log 0=0, used in for example formulas for entropy.

Re: 0^0

#17
I understand the "math"...the numbers...the work on paper. But how does that translate to something useful in the real world? That, after all, is what useful math helps us do...solve problems for the real, tangible world. Saying that 0^0 = 1 is a cool math game; but translate 0 into something in the real world (i.e. nothing, none, etc.)...and trying to make something out of it other than 0 or "indeterminate" starts to make less sense.

Re: 0^0

#18
Whenever you try to cross-breed an apple tree with a donkey, you get nonsense.

But for convenience, whatever the offspring is, we may call it a donkapple.

That's they beauty of math.

Re: 0^0

#19

Missing Q and A: But if mathematicians insist it is 1, why do high school teachers act like they know more than the mathematicians do? A: They don't. The statement that mathematicians uniformly say it is 1 is simply false. My high school teacher had a PhD in math, I think it's fair to say she was a mathematician. And yes, she said it was undefined.

I thought "most of the time" was implied in these sorts of things by now. And you will note the mathematicians don't "say it is 1"... they say they are choosing to follow the convention of defining it as 1, with reasons listed below.

I could come up with whatever crazy definitions in math I wanted to, and sometimes even get useful results. However, this view is not... convenient for teaching, so they pretend that you are learning "math", as opposed to "a particular math".

Re: 0^0

#20
post #15

Students: Let's come up with some crazy proofs based on our individual levels of understanding. Teachers: Let's do it by the book and come up (somehow) with conflicting answers. Mathematicians: Yeah, sorry guys. We made it all up. Pretty much captures most mathematicians I know.

Definitions in mathematics are used to make the language describing abstract concepts elegant, as explained in the entry. However, definitions aren't chosen all willy-nilly - there are good arguments why definitions are adopted, as should have been seen in the article.

Sort of like how we use terse symbols for everything because ink and papyrus is expensive.
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