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osoba

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Tbh any MOOC that "needs only 2-4 hours a week" is, by design, an entry level course and taking more of those won't help you progress.

On the other hand, you shouldn't lump together and dismiss all MOOCs as there are plenty of more advanced ones that will definitely make a difference. For example, 90% of MIT classes such as Intro to Statistics https://www.edx.org/course/fundamentals-of-statistics or CMU Deep Learning http://deeplearning.cs.cmu.edu/

Regarding that GNOME update, do GNOME developers just don't have any competence in UX design? That screencast is suggesting you need to click the activities button in the top left corner to be able to reveal a nav panel that's all the way at the bottom.

Similarly, right now, in current versions, in the file selection interface the Select button is in one corner of the window and Cancel all the way in the other.

Or the annoying unnecessary dialogue when you uncompress from an archive (no I don't want an app-blocking notification that the file extracted successfully).

I had a class that was so easy that most students didn't bother to show up for lectures. Near the end of the semester the profesor got angry that nobody came to his lecture and decided to retroactively grade attendance with 70% of the grade. Most students flunked. I was fortunate that his class was in between two others I was taking, so I attended about half of the lectures and passed it with a grade that corresponds to the American C+/B-

A few months ago I won about $200 worth of Amazon gift card codes. Since nothing from Amazon delivers to my country I decided to give them to an American friend of mine. I remember it was late for him when I sent him the codes over Facebook so he only used up one right away and then went to sleep.

The next morning, however, the other coupons were all used up. He claims nobody else has access to his FB messages and I never bothered to actually check the validity of the codes on Amazon, so there is enough room for plausible deniability, but this coincided in time with this reddit post https://www.reddit.com/r/privacy/comments/79x7u3/facebook_em... and now there's that nagging feeling in the back of my mind that some underpaid 3rd world facebook employee read through the messages and decided to use the codes themselves.

I don't know, this is all probably a stretch, but that moment reached a new low for Facebook in my mind (not that my opinion of them was high before).

Maybe this is a good opportunity for Firefox to abandon its "forced mediocrity" model.

The vanilla installation of Firefox lacks basic UI components (mouse gestures for example), lacks session management, and the bookmark and history interfaces look like they were made in 1995.

When you click an old entry in History I don't understand why it's so difficult for the selection to stay near the formerly clicked item, instead of it selecting the top most entry forcing you to scroll all the way down again if you want to open another entry that's near the previously clicked entry.

Why can't Bookmarks employ a simple logistic classifier? OK I've stopped using Firefox's bookmark system a long time ago (because its so shitty) but if I were to be still using it I would expect the browser to be smart enough to figure out that if all my bookmarks from a certain site are in a specific bookmark folder that most likely means this new bookmark from that same site should go there and should be offered as the 1st choice.

Now, yes, of course you can add all these features in a slow JavaScript-based addon which will eat your memory and cpu time and allow the Firefox team to blame the addons when something goes wrong with Firefox, but at some point you have to reconsider if this is such a good idea.

Sure very few people use mouse gestures in Firefox and adding them out of the box could be interpreted as bloat, but maybe if more users even knew what mouse gestures were and how useful they are, they would start considering them a fundamental aspect of a browser's interface and not just a fancy knick-knack.

I miss the old Opera so much :(

Those look more like proofs with pictures, than proofs by picture, but I'm too lazy to get involved into the obscure notation of that book and check whether a random proof from the book would be equivalent to a modern proof from a standard textbook.

Altough, judging by the old timey language of the book, it's possible the book predates Hilbert's axiomatization of Euclidean geometry and the proofs in it were good enough for the standards of its time.

In modern mathematics proof by picture generally means you've drawn / pointed out a single example, possibly wrongly or in a way that doesn't generalize, and because you've shown that one example holds you assume all possible examples hold. That, obviously, needs not be the case.

Proofs by picture arent proofs though. And how would you even convey by picture that two line segments are of the same length. Or that if you drew C and D as separate points they turn out to be the same point?

It's actually the other way around. Mathematical notation used to be very much language-like and tedious to read. As time went by (and math became more complicated) notation was developed to make it more succinct and easier to understand. (And sometimes the more succinct notation helps to develop new insights. The change from Roman to the Indian/Arabic number systems made calculations easier for everybody) https://en.wikipedia.org/wiki/History_of_mathematical_notati...

Compare the two following statements:

One from Euklid's elements (written 2.5k years ago):

"Given two straight lines constructed from the ends of a straight line and meeting in a point, there cannot be constructed from the ends of the same straight line, and on the same side of it, two other straight lines meeting in another point and equal to the former two respectively, namely each equal to that from the same end."

And my attempt of translating the above, in what should effectively be Hilbert's notation (19th-20th century):

If there are two triangles ABC and ABD where AC=AD and BC=BD and C and D are on the same side of AB then C and D are the same point.

Which one was easier to parse in your mind?

As a bonus try rewriting this formula using longer variable names and tell me how legible it would look http://i.imgur.com/wCWkyNL.png (it's from a proof of one of Syllow's theorems https://en.wikipedia.org/wiki/Sylow_theorems )

U, V: vector spaces

u, v: elements of vector spaces

G, H: groups

g, h: elements of groups or

g, h: homomorphisms, isomorphisms etc

e: group identity

K, F: fields

I: ideals

f: functions

(x): sequences

x_i: i-th element of a sequence

A, B: matrices

It all depends on the context it's used of course

A tangible benefit for a young English-speaking native to learn, for example, German, French or Norwegian would be the ability to obtain university education for free (or near free ~ $50-$100 per semester, compared to $10k-$50k for USA or UK)

Good point. So maybe browsers should make the full version the default and then add the following options for more tech savvy users (and users can set the permanent default or per website setting):

1) full mode (all JS is enabled)

2) lite mode (only the bare JS is enabled, no tracking possible)

3) suggested mode (a machine learning algorithm decides what is really needed to be enabled and what is there for tracking purposes)

4) manual mode (somewhere in the settings you can tick and untick verious JS APIs that you want enabled and disabled, like websockets, WebGL etc)

Random idea: Couldn't browsers have two modes of browsing, one lightweight one where only the most basic of JS features are enabled by default (this is something that 99% of websites actually need) and the full version where everything is enabled. The lightweight one is the default state and the users can manually switch to full version. Or even better use logistic regression or a neural network to decide when a website genuinely needs advanced features and when it's just to track you. As a bonus the lightweight mode would also probably render much faster? How realistic is this? What would be the downside?

I've been learning french on Duolingo for a about a year now. Usually I take one or two 5 minute lessons per day for a week and then spend a week "strengthening skills" (reviewing old material). It says I am on 54% fluency atm.

A few weeks ago I tried going though a math course in french (Initiation à la théorie des distributions on Coursera) and was surprised that I actually managed to understand it. (although I have to listen to it at 1x speed and with french subtitles so it is much slower than leaning in english)

Theorem of the Day 10 years ago

I think tau was used on purpose in that article to avoid confusion with the prime counting function, typically denoted pi (unrelated to the constant pi)

For Calculus check Coursera - the Ohio State course if you really don't know absolutelly anything, then do the Penn State course(s) Calculus in a Single Variable

For Linear Algebra check Gilbert Strang's course on MIT OCW

For Probability/Statistics either John Tsitsiklis' course on MIT OCW (or even better on edX when it re-runs) or Harvard's Statistics 110: Probability course on youtube

The level of multivar calculus you'll need is really minimal, just google these terms "partial derivative", "total derivative", "differentials and integrals commute" ("Symmetry of second derivatives", "Fubini's theorem") or take the vector calculus course from MIT OCW

You're correct. There is one object in all of mathematics that isn't defined (you've got to start from somewhere), it is just assumed that humans implicitly understand this concept, and it's the concept of a set (denoting a collection of objects).

Along with it, certain properties of this object are assumed (among them the ability to choose an element of a non empty set - this is typically called the axiom of choice). For a full list you can take a look at http://mathworld.wolfram.com/Zermelo-FraenkelAxioms.html

The set of real numbers most certainly exists, it is defined as the unique such set (up to an isomorphism) that satisfies the following properties:

It is at the same time a commutative additive group and a commutative multiplicative group such that the two group neutrals aren't the same. Furthermore the multiplication distributes over addition.

There exists a total order relation such that the addition distributes over the order relation and multiplication agrees with the order relation (if (0 leq x) and (0 leq y) then (0 leq x*y)).

Another axiom is required, which comes in many forms (all of which are equivallent) so take your pick, for example the supremum axiom https://en.wikipedia.org/wiki/Least-upper-bound_property

You can read about any of this in any texbook of real analysis (for example Spivak or baby Rudin).

If the axiomatic formulation of real numbers doesn't appeal to you, there is another way to define real numbers, namely to contruct them from natural numbers (and you seem convinced that natural numbers indeed exist). You can read about that in the appendix to chapter 1 of baby Rudin (Principles of Mathematical Analysis by Walter Rudin).

For probability/statistics you could also use the MIT Course https://www.edx.org/course/introduction-probability-science-...

Same course if you prefer the classroom lectures http://ocw.mit.edu/courses/electrical-engineering-and-comput...

Or if you want more rigor you can go through these notes that cover the same material but in a more formal way (via sigma algebras and measure theory) http://ocw.mit.edu/courses/electrical-engineering-and-comput...