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#1 Re: Coder's Corner » Trying to approximate factorial function using Lagrange polynomial » 2023-01-06 21:18:27

Hi Keckman, I just briefly looked at your code. From your definitions: You treat the partial polynomials as *numbers* (correct me if I err, but the extended data type is not suitable for polynomials but just for real numbers). Well,  the factorial of 1000 e.g. would require about 8530 binary digits ... After all, you have to deal with polynomials using tuples / lists of their respective coefficients.  Hope this is not too patronizing: But the Lagrange polynomials are a real pain; why not use the Newton polynomials (look for "divided differences"). But I'm afraid you won't get good approximations in this case just with say a 3rd degree polynomial.

#2 Euler Avenue » Two sequences and the exponential function » 2022-08-28 20:49:15

theshire
Replies: 1

It all started out some years ago when I read how the number e was introduced / defined. I thought to myself: Hey, why not explore the sequences


for some real number r.

Let

such that
. Define

Then for some


Thus

Therefore

Looking at the sequence of partial sums

:

Hence

So

Therefore

Now pick some positive real number r. Define

Then for all integers n such that



So if you pick some
, then there exists an integer N such that for all integers greater than N:

Hence

Define


for
.

So finally we get

#3 Re: Euler Avenue » What do you think is the worst way to learn mathematics? » 2022-08-28 17:55:32

From books written in Bourbaki-style! -- I am not on 'very friendly terms' with algebra; yet I like the book of B. L. Van der Waerden. Now take any oh so modern book -- say about group theory, with several pages of notation and what not ... horrible. I think Gauss said / wrote: "We need notions, not notations!" (btw, you can sing that on "another brick in the wall" :-)).

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