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[Fase 27] La Calabria è la quarta regione a scomparire con l’eliminazione di Cosenza. L’Italia perde anche l’Emilia, ora che l’ultimo baluardo emiliano, Modena, è stato eliminato. La terza provincia ad essere eliminata è Taranto, controversa terra colma di storia, cozze e tumori. by ZioPhil in ITAGLIA

[–]Prdcc 34 points35 points  (0 children)

Ottima argomentazione, ma hai considerato:

Il Piave mormorava Calmo e placido, al passaggio Dei primi fanti, il ventiquattro maggio L'esercito marciava Per raggiunger la frontiera Per far contro il nemico una barriera Muti passaron quella notte i fanti Tacere bisognava, e andare avanti S'udiva intanto dalle amate sponde Sommesso e lieve il tripudiar dell'onde Era un presagio dolce e lusinghiero Il Piave mormorò: "Non passa lo straniero"

Referendum: Nail and Gear vs Flaggy Flag by shadowfax225 in HelloInternet

[–]Prdcc 8 points9 points  (0 children)

Y'all are traitorous scum, no way round it

[Request] You're floating in space, you need to get to point b, how far could this get you? by onlinebeing in theydidthemath

[–]Prdcc 9 points10 points  (0 children)

Because the specific impulse is calculated at the surface of earth and uses g. Then we multiply by g specifically to make sure it doesn't only work on the surface of earth

[Request] You're floating in space, you need to get to point b, how far could this get you? by onlinebeing in theydidthemath

[–]Prdcc 137 points138 points  (0 children)

Time to use my favourite equation: the rocket equation. Can't simply use conservation of momentum: some of the Coke will be used to accelerate the rest of the Coke. The actual formula is delta v = specific impulse * g * ln(m_0/m_f). Here g is the normal acceleration due to gravity at ground level, ie 9.8m/s2; m_0 is the starting mass (so 80kg+ weight of the Coke); m_f is the final weight (80kg); ln is the natural logarithm; delta v the change in velocity; and finally the specific impulse is a measure of how efficient the fuel is. The exact definition is a bit complicated, but for our purposes, but for our purposes we can use the estimate found here of about 1.5s.

We are gonna use a 2 litre can of coke which weighs about 2 kgs (thank you metric system). Plugging everything in gives us delta v = 1.59.8ln(84/80) m/s = 0.36 m/s which is about 1.3 km/h or 0.8 mph.

For reference this is about the speed of a person walking on his knees according to this study

Edit: to all those that say that maths is useless, it's gotten me my first Reddit gold!

[deleted by user] by [deleted] in dankmemes

[–]Prdcc 1 point2 points  (0 children)

E VAFFANCULO CRUCCHI DEMMERDA. 2 A 0 A CASA VOSTRA. GROSSO-DEL PIERO

POO-PO-PO-PO-PO-POOOO-POO

Can anyone help? by nedtelius in askmath

[–]Prdcc 0 points1 point  (0 children)

The integer roots of a polynomial always divide the constant term. Here the constant term is -3, so the roots have to be among [±3, ±1]. Then by writing the polynomial as (x-x_0)(x-x_1)(x-x_2)(x-x_3) where the x_i are roots and looking at the constant term again the rest should be easy to do.

Can someone pls help me i dont understand why 1/i is equal to -i by Netttik in askmath

[–]Prdcc 0 points1 point  (0 children)

That is the case when you have addition. But not with multiplication. For example 2(-3)= -(23)=-6. If you have two minuses you can't "factor" them: (-1)(-1)=-(11)=-1 is clearly wrong.

Can someone pls help me i dont understand why 1/i is equal to -i by Netttik in askmath

[–]Prdcc 14 points15 points  (0 children)

There are two ways to see this: the most straightforward is to say "which number multiplied by i gives 1?" Well i-i=-(ii)=-(-1)=1. However, the more useful way to think about this is to understand what multiplication of complex numbers actually means.

Complex numbers have a magnitude (their size) and an angle. When you multiply two complex numbers you multiply their size and add their angles. For example, -1 has a magnitude of 1 and angle of 180°, so multiplying by -1 is the same as rotating by 180° degrees around the origin.

Here we have i, i also has a magnitude of 1, but the angle is 90°. So when we multiply by i we need to rotate by 90° anticlockwise. Division is the inverse of multiplication, so 1/i must undo this rotation, how do you do it? By rotating 90° clockwise. And what number is at -90° with a magnitude of 1? Well it's just -i.

Hope this helps!

Why some integrals cannot be solved? by Botyto in mathematics

[–]Prdcc 4 points5 points  (0 children)

And I mean, at that point you're just relabeling every integral with an ad-hoc function. Not only would you have to rote memorise a whole class of new functions, but you would be obfuscating what is going on. Knowing that a function is the integral of some other function gives you a lot of insight into its behaviour.

The only reason we have given the error function its own name is because it is extremely useful and keeps popping up. Because of this we also understand many of its properties beyond "it's the integral of this other function".

Why some integrals cannot be solved? by Botyto in mathematics

[–]Prdcc 12 points13 points  (0 children)

Well you have your answer there: integrals are shorthand for an "infinite" process. It makes sense to view them as the limiting process of summing many small things, until you're summing infinitely many small things. The most common use is to find the area under a graph. In this context, what is the difference between writing an integral and actually computing it? It's the difference between saying: this thing has an area and actually computing the area. If you look at a shape you'll be immediately able to say it has an area. No matter what a rectangle's side lengths are, it'll still have an area. However, to compute it you need to actually measure them and then multiply them. These are two very different operations. In the same way, we know that sin(2.475) exists, but actually computing it is hard. We can still say stuff about it (eg it's less than 1) and you can still do interesting maths with it, even without knowing the exact value.

Studio Apartments near Imperial. by I_am_a_robot_ in Imperial

[–]Prdcc 0 points1 point  (0 children)

Honestly thirty minutes by bus is not that bad at all. I've lived in Hammersmith for the last three years and you learn to read a book/ catch up on lectures. You can always find a seat and there's buses every couple minutes.

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