# Welcome HOW360°, Questions & Answer

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## "what's in store" vs. "what's in stall"

I think this is probably just one of those phrases people get wrong, such as "for all extensive purposes" - but I just found this on a cafe web page: This question asks the meaning of &qu

english-language

## Ηow can I replicate the sound οf this instrument?

If you go ahead and watch this video, the guy with the drums has a percussion instrument with his right hand that produces the shaky sound, kind of like the maracas. What is it called? Is it po...

music

## Computing Curvature via Cartan Formalism

Given a metric $g_{\mu \nu}$, one can select an orthonormal basis $\omega^{\hat{a}}$ such that, $$ds^2= \omega^{\hat{t}}\otimes\omega^{\hat{t}} - \omega^{\hat{x}} \otimes \omega^{\hat{x}} - ...$$ By

physics

## How to improve self discipline when starting from nothing

It seems that I have no ability to be productive. Outside of the occasional week where feeling accountable to somebody else has kept me on task, I have never had the self discipline to accomplish

personal-productivity

## Verification of identity $2\sum_{m,n\geq 1\,;\,m>n}\frac{1}{m^k n^k}=\left(\sum_{n\geq 1}\frac{1}{n^k}\right)^2 -\sum_{n\geq 1}\frac{1}{n^{2k}}$

Is this identity true? $$2\sum_{m,n\geq 1\,;\,m&gt;n}\frac{1}{m^k n^k}=\left(\sum_{n\geq 1}\frac{1}{n^k}\right)^2 -\sum_{n\geq 1}\frac{1}{n^{2k}}$$ If so, how to prove it? Could you provide me a

mathematics

## Closed form of $\int_{0}^{\infty} \frac{\tanh(x)\,\tanh(2x)}{x^2}\;dx$

I have homework to evaluate this integral $$I=\int_{0}^{\infty} \frac{\tanh(x)\,\tanh(2x)}{x^2}\;dx$$ Here is what I have done so far. I tried integration by parts using $u=\tanh(x)\,\tanh(2x)$ ...

mathematics

In English, when presented with a list (real or imagined) or answers that could be given to a question, and the correct one is not given, we will say that somebody has given "the wrong answer&quo

english-language

## When something sounds too good to be true, it is or isn't?

I'm having a hard time understanding why the phrase is when something sounds too good to be true, it is and not when something sounds too good to be true, it isn't Because "wh

english-language

## Does apologizing entail recognizing being at fault?

Consider this example: I'm sorry if you got the impression that I meant to insult you. That was not my intention. Would it be correct to say that the above person apologized? All the dicti

english-language

## Isn't this rude? Or am I wrong?

I recently saw this statement when I unsubscribed an email from DiGi. We're sorry to see you leave (but you know where to find us again for the latest information, hot updates and news!) I

english-language

## An alternative proof for sum of alternating series evaluates to $\frac{\pi}{4}\sec\left(\frac{a\pi}{4}\right)$

How does one prove the given series? $$\sum_{n=0}^\infty\left(\frac{(-1)^n}{4n-a+2}+\frac{(-1)^n}{4n+a+2}\right)=\frac{\pi}{4}\sec\left(\frac{a\pi}{4}\right)$$ This series came up in xpaul's calc

mathematics

## How to understand the curvature of this metric?

Suppose we have the metric $ds^2 = dr^2 + \alpha^2 d\phi^2$, where $\alpha$ is a constant, $0 \leq r \leq \infty$, $0 \leq \phi \leq 2 \pi$ and we identify points $\phi = 0$ with points \$\phi = 2...

physics

## How to derive the schwarzchild metric?

I'm having trouble differentiating the following when making a change of co-ordinates to determine the Schwarzchild metric. $$r'^{2}=r^{2}C(r)$$ Then taking the total derivative of both side

physics

## How do your busiest people transfer their knowledge?

This question was originally posted on Programmers SE. I've placed it here based on advice in the comments. We have recently polled our company wide wiki users and found out that there are two la

personal-productivity

## Stars at near break-up rotation rates

Accretion discs are ubiquitous in astrophisics. As a direct corollary, they are important for the following question. Consider the following model, representing one of the most simple models for

astronomy

## How rude is "to eat like a pig"?

How rude is it to say : People eat crabs like a pig. Maybe it's not rude in plural sense like the above example but when you talk directly to someone? Also other terms which relate humans t

english-language

## Why is quasineutrality required for a gas to turn into a plasma?

Why is quasineutrality a required condition for a plasma to exist? Quasineutrality means that no density of electrons and ions should almost be equal but not exactly equal. Can anybody explain this...

physics

## Does Izumi Shinichi parasite suffer from a lack of power because of his injury?

After his parasite completely heals his heart and regenerates his arm, does he lose any abilities except the power to locate other parasites when he's asleep?

anime

## Can anyone tell me where this is from or if it is just art?

Hey all, need help with something - as the title states, can anyone tell me where this is from? Thanks.

anime

## Is there more than 1 types of light novel to Spice and Wolf series?

I've always thought there is only 1 type of light novel for this series (which is translated to other languages). But I saw in Amazon that they offering to buy 3 types of the same light novel. ..

anime

## can't remember a anime on toonami from like 3 or 5 years ago

I remember there was these two teens they each had magic (one boy and one girl ) one made boxes that anything inside would disintegrate and the girl would make a line and it would cut anything. They

anime

## I want to know the name of the manga

my friend told me great yaoi manga It's about a rich guy whom his lover left him And he searches for him everyday at the train station until he meets a guy who looks like him, and then they become ..

anime

## Why do almost all anime series have a “going to the beach” episode?

Not many anime have a dedicated episode for going to the cinema, concert, amusement park, circus, football match, camping or any other activities. But, almost all of them spare at least one of their .

anime

## Is Rui a boy or girl?

In Gatchaman Crowds, when we see Rui outside he/she is wearing a blonde wig of either long hair when looking like a punk rocker or short hair when wearing a blue dress. When Rui is getting dressed to

anime

## Why did Aoi-sensei expect Shouko to leave with Nami?

in the Grand Route of Aoishiro, after arriving on Urashima with Nami Shouko gets a call from Aoi-sensei who asks where they are. After finding out that Shouko is on Urashima she also confirms if Nami

anime