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u/cond6

SPP: What's the square root of pi brud? Go ahead. Make my day.
▲ 12 r/infinitenines

SPP: What's the square root of pi brud? Go ahead. Make my day.

Locked immediately because not a genuine question, but here's an answer:

https://preview.redd.it/yjple23f570h1.png?width=1310&format=png&auto=webp&s=981ead13c89125625a54ecd7192729021638075a

Can you please do the same for sqrt(0.999...)?

And before you flip out over not writing down digits, recall that a number is not the same thing as its representation. The number 1/2 can be expressed in many ways, but the number is an abstract concept. We don't care about decimal representations other than being able to express in a convenient but by no means unique way a number. Decimal representations aren't a number. They're a way to write down a number to convey the abstract notion from author's brain to reader's brain.

So an infinite series is how pi is defined. The integral above is one way to express the square-root of pi. And I usual express answers that involve root-pi in terms of root-pi. For example the probability density function of a normal random variable. Or, if z~N(0, sigma) then E(|z|)=sigma*sqrt(2/pi). I don't write sigma*sqrt(2/3.14159....) because I'm not an animal.

But back to the question: What is a the square root of 0.999...?

Don't engage in embarrassing "I know you are, but what am I" arguments. I gave you an expression for root-pi other than root-pi. Can you do the same?

Edit: typo.

reddit.com
u/cond6 — 4 days ago
▲ 11 r/infinitenines

SPP has recently been posting riffs on the theme of:

>limits don't apply to limitless summations.

and

>Limits don't apply to the limitless dum dum.

for example here, though there are many examples in other threads, every time someone points out that the standard definition of an infinite sum is as the limit of the partial sums. If the partial sums converge the value of the limit is assigned to the sum, and if it doesn't converge but diverges to positive or negative infinity the value of the infinite sum is informally set to plus or minus infinity (if the series is say n*(-1)^n it oscillates and is given neither value).

However it is important to note that words have multiple meanings. The best example of this that I know of is Four Candles. Love the Two Ronnies.

The English word limit has many meanings that depend on context. SPP tries a misdirection when he implies that one definition is used when another is clearly implied.

The standard dictionary definition of limit "the greatest amount, number, or level of something that is either possible or allowed". I agree such use of the word limit to refer to the infinite or infinite summations is wrong.

However it is dishonest and disingenuous to try to impose that interpretation on the actual use of the word limit in the context of infinite summation. In mathematics "a limit is the value that a function (or sequence) approaches as the argument (or index) approaches some value" (from Wiki). So the limit of the function f(n)=n as n approaches infinity is infinity. The limit very literally is infinity. So you saying "limits" don't apply to infinity in this context says "infinity" doesn't apply to infinity.

SPP is that your argument? Can you be honest and not distort what people mean when they say we do infinite sums by taking limits of partial sums?

u/cond6 — 8 days ago