19

Numerical fractions 2/3 = две третьих or две трети The numerator of a fraction is always a cardinal number and the denominator is an ordinal number in Genitive (singular if the numerator ends in "одна" and plural if that's not the case). Always use feminine when the form exposes gender. For quarters and thirds you can also use "одна треть"...


8

В словарь древне-русского языка Срезневского есть статья про слово черта: ЧЕРТА 1) Протяжение, имеющее одну длину без ширины и толщины, линия. Иота едина, или едина черта не прейдет от закона. Провесть черту. 2) Стар. Пограничная линия; рубеж с укреплениями. Велели столнику и воеводе... Колычевскому быти по Белогородской черте в Олшанску. 3) Действие, ...


7

I don't think there's any set rule, but as a native speaker I can advise the following options. First you have to know that in Russian the decimal separator is comma , (pronounced запятая, colloquially и), not period .: 0,333... – ноль и три, три, три [и так далее]... 0,333... – ноль, запятая, три, три, три [и так далее]... More scientific way: 0,333... = ...


7

Here's my attempt of an answer (I might have to post it unfinished and come back to it later). I assume that your native language is English. Take as well as Russian взять / брать are the examples of highly polisemous verbs. From here: This paper attempts to show what the definition of a word should look like, in order to be of use to AI programs such ...


6

Intuitively, I do feel that there's a preference for putting орёл first, and a quick exact phrase search on Google confirms it: орёл или решка is about three times more frequent than решка или орёл, and the prevalence of орёл и решка over решка и орёл is astronomical. However, I don't think this has to do with the alphabet. It might be the same case of a ...


6

The two names, йот and жи, are equally correct, this table lists them both under "классическое русское название буквы". I don't go in for mathematics a lot so as to comment on their disrtibution, but when I studied at the mathematics school in the early 90s, we used жи.


6

A fraction x/y is pronounced by mathematicians as икс на игрек. Moreover, a product xy is pronounced the same way if you want to include a word representing the operation (often you do not and would pronounce xy simply as икс игрек; a case when it is natural to pronounce the operation in a product would be x*2, unlike 2x -- in fact if you tried to pronounce ...


6

The question in the title and the question you wrote are not quite the same. The question in the title sounds like it is asking "what case is used after mathematical objects denoted by letters like G, H, etc.", while the question you wrote is asking "what case follows a counting variable"? [EDIT: The question in the title was later changed to match the ...


6

The very fact that some noun has valid plural form doesn't mean that that plural is in active use. In practice it can be used quite rarely. Consider, for instance, "сметана" - we can construct a valid sentence with it, like: Меня удивило, что к столу подали самые разные сметаны - были тут жирные, густые, и такие, что по консистенции напоминали ...


5

I believe i would answer exactly as the answer key shows, which in your opinion is incorrect. I guess the translator/s thought that when English speakers say 'rectangle', it means 'oblong in their language/dialect I do envision such a possibility. In Russian square is квадрат while rectangle is прямоугольник (named oblong rectangle in your description)...


4

@DmitryAlexandrov: did those links to English examples help you? Yes, they helped of course. I’ve googled around the Web and made sure that @vix2 is absolutely right: cutoff as a verb would be обрезать, as a noun – обрезание, though you may think that the latter sounds a bit funny (most common meaning of обрезание is circumcision :-). You can found it both ...


4

"Интеграл обрезается на высоких частотах в связи с конечными " "Интеграл обрезается на дебаевской моде" etc.


4

I learnt physics, and I don't remember that on lectures anyone called J йот. As far as I know, in physics, as well as in mathematical analysis lectures, J is жи, unless something changed in recent 20 years. Also, looking at the lecture, it seems the lecturer used both J (жи) and G (же). Possibly he calls the former йот in order to avoid the confusion.


4

Imagine the teacher stands in front of the class. Addressing the audience the teacher will never say Сколько будет восемь на семь? but always Сколько будет восемь умножить на семь? If a teacher examines complex expression 100 + 8 × 7 - (5 + 12) standing at the blackboard and points at (5 + 12) he will say сколько будет пять плюс двенадцать?, but highly ...


4

I think most people will realize this form if listener knows that you talking about math. Also, a little bit more precise, you can say "восемью семь" or "трижды семь" for 3 * 7.


4

I'm not familiar with the term but comparing the definitions you linked and Блюмин С.Л 2.4 (17) and (18), looks like the translations are: infinite distributive - бесконечно дистрибутивная join-infinite distributive - брауэрова meet-infinite distributive дуальная брауэрова


4

Итак, есть четыре основных связанных с понятием number термина: Цифра - знак для числа, подобно тому, как буква - знак для звука (1, 2, 0); Число - собственно, математическое понятие; Номер - число, приписанное определённому объекту, обычно порядковое (дом номер 2 и т.п.); Числительное (также известное как имя числительное) - одна из традиционно выделяемых ...


3

First thing - "от" is not a verb, but preposition. As for usage with derevatives - mathimatical text in Russian is very hard to read due to lots of grammatics dependences between close and distant phrases and terms. While in simple text there is no difference between using and not using "от" (it's a matter of taste), in complex text this preposition helps ...


3

In a mathematical context, there is no practical difference. Where "от" is explicitly used, it just (in my view) reinforces the genetive case. In some phrases it is customary; in some not ("сумма от чисел" is never used, it would have a different (non-sensical) meaning, see below). You can more often see "от" when there is a dependent word, such as "...


3

Others have commented on the correctness of the name. I'll get to why you can hear both (and probably more) versions. In the Soviet Union (and in modern Russia still), the average knowledge of foreign languages was unfortunately very limited. Since the Russian alphabet is usually different from those used in foreign languages, a lot of people can't even read ...


3

The grammatically correct form is only n-й. Acoording to entrenched tradition accretion suffix must be one-letter if the last letter of numeral follows by vowel: 5-й день (пятый день), 25-я годовщина (двадцать пятая годовщина), в 14-м ряду (в четырнадцатом ряду). It must be two-letter if the last letter of numeral follows by consonant: 5-го дня (пятого дня), ...


3

In the meaning of "vary, become different" the verbs are synonymous, with both used in academic style with no difference in connotation — i.e. the choice of a verb in a particular sentence is up to the author (for example, to avoid using only "изменяться" several times in a row).


2

When counting there are three plural forms when the object being counted is the subject of the sentence. Let n represent a number. the last (units) digit of n is 1 but the last two digits are not 11: use nominative singular один кот, двадцать один кот, сорок один кот, тысяча один кот... the last (units) digit of n is 2, 3, or 4 but the last two digits ...


2

имеются n абелевых групп G_1,G_2,...,G_n, таких что... Generally, in Russian academic writing "we have groups" is not used, instead we write "there are groups". It's a matter of style, rather than grammar though. I'm not a linguist, but nominative plural would be my answer, because I test it with a question "имеются кто/что?"


2

I would say "икс делённое на игрек" or "икс делить на игрек". If from the context it is clear that multiplication excluded, you can say just "икс на игрек" but this also can mean multiplication.


2

Mathematicians (at least in Russia) do not specially learn and/or practice Greek calligraphy, except while handwriting math formulas. So the quality of average handwriting may be somewhere between bad and ugly. But I'm rather surprised to hear that you found "sigma" and "delta" not differing at all. That could only be due to someone's personal mistakes. P.S....


2

Умножить на is formal and "official" name of operation, на is colloquial abbreviation. Also, на could be abbreviation of division (разделить на or делить на), that's why it can be unclear, when you say just восемь на семь. But with context, there is no problem: Таблицу умножения выучил? Сколько будет семь на восемь? Here is obviously multiplication. And ...


1

No extra details. Some people use 'от' when they talk about algebraic or trigonometric functions (but not arithmetic though). So 'Производная от функции', 'Интеграл от функции' are acceptable as well as 'Синус от нуля' or 'Экспонента от функции'. However, if you see it in a written text it probably means that author has poor grammar. 'Сумма от чисел', '...


1

In a casual or semi-casual conversation about math взять can work as a synonym for вычислить. I can easily imagine a math lecture containing phases like Теперь давайте возьмем от этого выражения логарифм. Берите от функции квадрат, чтобы в задаче на оптимизацию был подходящий градиент. Same for взять квадрат, интеграл, сумму, корень, когомологию. ...


1

In my personal experience (I studied in Moscow in applied maths) I've seen people writing both versions of sigma, but "Russian" one really was more common. And also there is a rather common scenario, when the lecturer first writes sigma with short tail, then someone asks, what letter it is (or the writer notices himself, that it is not clear enough), and ...


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