I want to enter the new year, not only freeing myself from debts for ...
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The account appeared when a person needed to inform his relatives about the number of objects he discovered. At first, people simply distinguished one object in front of them or not. If the subject was not one, then they said "many". The first concepts of mathematics were "less", "more" and "the same". If one tribe exchanged caught fish for stone knives made by people of another tribe, it was not necessary to count how many fish they brought and how many knives. It was enough to put a knife next to each fish for the exchange between the tribes to take place.
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The simplest counting tool was the fingers on the hands of a person. With their help, you could count up to 5, and if you take two hands, then up to 10.
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One of these counting systems subsequently became commonly used - decimal.
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In ancient times, people walked barefoot. Therefore, they could use both fingers and toes for counting. Thus they could, it would seem, only count to twenty. But with the help of this “barefoot machine”, people could reach much larger numbers, 1 person is 20, 2 people is twice 20, and so on. There are still tribes in Polynesia that use the 20th number system for counting.
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It was difficult to memorize large numbers, so mechanical devices were added to the "counting machine" of the arms and legs. Many counting methods were invented: In different places, different ways of transmitting numerical information were invented: For example, the Peruvians used multi-colored cords with knots tied to them to memorize numbers.
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The need to record numbers appeared in very ancient times, as soon as people learned to count. The number of objects was depicted by drawing dashes or serifs on some solid surface: stone, clay, etc. = People used to draw sticks on the walls and make notches on animal bones or tree branches
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Archaeologists have found such "records" during excavations of cultural layers dating back to the Paleolithic period (10 - 11 thousand years BC). This way of writing numbers is called a single ("stick", "unary") number system. Any number is formed in it repetition of one sign - units.
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A single notation for such numbers was cumbersome and inconvenient, so people began to look for more compact ways to denote large numbers. There were special designations for "fives", "tens", "hundreds", etc. = The more grain people gathered from their fields, the more numerous their herds became, the larger numbers they needed.
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The system of such signs among the Egyptians was very clear. The Egyptians came up with this system about 5,000 years ago. This is one of the oldest numbering systems known to man Egyptian numbering
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Like most people, the Egyptians used sticks to count a small number of objects. Each unit was depicted by a separate stick. The Egyptians tied cows with such fetters. If you need to depict several dozen, then the hieroglyph was repeated the required number of times. The same applies to the rest of the hieroglyphs. 1 10 This is a measuring rope, which was used to measure land after the flood of the Nile. 100 1000 Lotus flower Egyptian numbering tadpole 100 000 1 000 000 10 000 000 The Egyptians worshiped the god Ra, the god of the Sun, and probably depicted their largest number in this way. Seeing such a number, an ordinary person will be very surprised and raise his hands to the sky attentive
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This is the most common numbering today, which we currently use. The currently used numbers 1234567890 were established in India around 400 AD. it began to be used in Europe, but in Europe they became known thanks to the works of Arab mathematicians, and therefore the name "Arabic" was established behind them, although the Arabs themselves use completely different symbols to this day. Arabic numerals: In Russia, Arabic numeration began to be used under Peter I (Slavic numeration was preserved until the end of the 17th century) Arabic numeration
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The word "figure" (in Arabic "syfr") was also borrowed from Arabic, meaning literally "empty place". This word was used to name the sign of an empty category, and retained this meaning until the 18th century, although the Latin term " null" (nullum - nothing). The form of Indian numerals has undergone many changes. The form that we now use was established in the 16th century. According to the Moroccan historian Abdelkari Boungir, Arabic numerals in their original version were given meaning in strict accordance with the number of angles that the figures form.
Math lesson
Roman numerals
multi-digit numbers
using Roman numerals.
Lesson objectives:
- Learn basic Roman numerals
- Learn how to write multi-digit numbers in Roman numerals.
- Write numbers in Roman numerals
- Read numbers written in Roman numerals.
Key numbers
Rules for reading and writing numbers in Roman numeration
- The number must be read from left to right.
- If the smaller number comes before the larger number, then it must be subtracted from the larger number.
- If a larger number comes before a smaller one, then they need to be added.
- The same digit in a number entry should not be repeated more than three times.
The first flight lasted
108 minutes
It has been since the first flight
Cosmonaut Sergei Avdeev held in space
Went out into outer space
149 astronauts
Mutual check
- CVIII
- DXXXI
- DCCXLVII
- CXLIX
Read Pippi Longstocking's entries
In the country of Veselia CXXV inhabitants. Among them are LXX little oarsmen. On the island are DCC coconut trees and DCCL breadfruit trees. For the arrival of Captain Longstocking, the oars prepared CX necklaces made of shark teeth.
Independent work
- Level 1 Quests
No. 1 first table, No. 2
- Level 2 Quests
No. 1 second table, No. 2
- Level 3 Quests
No. 1 second table, No. 3
- Level 4 Quests
Mathematical dictation
XIV III CCXL CL XC DLX CD CII
10 4 3 240 150 90 560 400 102
Lesson summary
- In class, we learned...
- Most of all I liked …
- In life, this knowledge and skills ...
Homework
- No. 3,4 p. 24.
- Create a fun activity for your classmates using the Roman numeral rule.
- Find out what number the Romans wrote down on the temple building - MDCCLVI and what does it mean?
Roman numerals V.P. Dmitrieva "Gunbetova Karina Lecturer: Pavlikina F.A.
Definition of Roman Numerals Roman numerals are special characters used to write decimal places and their halves. To designate numbers in Roman numerals, 7 letters of the Latin alphabet are used:
Roman numerals are denoted by some letters of the Latin alphabet, namely: Number 1 - Roman numeral I Number 5 - Roman numeral V Number 10 - Roman numeral X Number 50 - Roman numeral L Number 100 - Roman numeral C Number 500 - Roman numeral D Number 1000 - Roman numeral M But it cannot be assumed that Roman numerals are the same as Latin ones. This statement would be incorrect.
Origin History The history of the Roman number system originates, of course, in ancient Rome, during the heyday of the Roman Empire. It was used more than two and a half thousand years ago and is used to this day. Roman numerals, as the main ones, have been used for a very long time. Two hundred years ago, in all business papers, only Roman numerals had to be written, since it was believed that Arabic numerals were much easier to fake. ten five
The essence of the Roman numeral system is that it uses uppercase Latin letters to designate numbers. But few people know that these letters were not chosen by chance. I - stands for one, this is one finger. V is five, an open palm on which we have 5 fingers. X is ten, two crossed palms on which we have ten fingers. Now the history of the Roman number system is not over.
Rules for writing numbers in Roman numerals - if a large number comes before a small one, then they add up (addition principle), - if a small number comes before a large one, then the smaller one is subtracted from the larger one (subtraction principle). The second rule is applied in order to avoid repeating the same number four times. So, the Roman numerals I, X, C are placed respectively before X, C, M to denote 9, 90, 900 or before V, L, D to denote 4, 40, 400.
It should be noted that performing even arithmetic operations on multi-digit numbers with Roman numerals is very inconvenient. Probably, the complexity of calculations in the Roman numbering system, based on the use of Latin letters, became one of the good reasons for replacing it with a more convenient decimal number system in this regard.
The Roman numbering system, which dominated Europe for two thousand years, now finds very limited use.
Roman numerals are used to denote: 1st century (XII century)
2.months when indicating the date on the monuments (21.V.1987) 21..1999
3.Time on watch faces
4. ordinal numbers
5.derivatives of small orders
6. To sign the sequence of notes
Roman numerals are very beautiful, and knowledge of this number system is necessary for a modern civilized person.
Thank you for your attention
