From the numbers, find the difference between the two numbers. Understanding whole numbers: rules, applications. The power of extracting numbers from the sum
For a complete analysis of those statistics, we introduce the terms and meaning, meaning the sense of action and the rule that can be derived from which action can be brought to conclusion. Let's look at practical applications. And let’s also look at the action seen in the geometric luminosity – on the coordinate line.
Here are the main terms that are used to describe everyday life, the same for any type of numbers.
Yandex.RTB R-A-339285-1 Viznachennya 1
Zmenshuvane- the whole number from which the day will be held.
Rising– an integer number that is identifiable.
Retail– the result of the viconnoy’s action.
To indicate the value itself, the minus sign is displayed and the placement between the changes is raised. All warehouse parts assigned to each other are registered with the view of equality. So, if you are given a number a and b, and when the number c comes out of the first one, the result will be written as follows: a - b = c.
The expression a – b is also significant as a difference, as is the final significance of the expression itself.
Sensation of whole numbers
On the topic of natural numbers, the interrelationships between the actions of the folded and the visible ones were established, which made it possible to identify the obvious as the search of one of the add-ons for the same sum and another add-on. It is accepted that the same substitution for all numbers is as follows: after a given sum and one of the addenda, another addon is assigned.
The meaning of the sense of seeing whole numbers makes it possible to confirm that c - b = a and c - a = b, since a + b = c and a, b, c are whole numbers.
Let's look at simple examples to reinforce the theory:
Let us know that - 5 + 11 = 6, so the difference is 6 - 11 = - 5;
It is acceptable, apparently, that - 13 + (- 5) = - 18 to - 18 - (- 5) = - 13 and - 18 - (- 13) = - 5.
Rule for identifying whole numbers
The meaning of the most significant replacements does not indicate to us a specific method for calculating the difference. Tobto. We can confirm that one of the known donations is the result of a difference from the amount of another known donation. However, if one of the dodanks appears unknown, then we cannot know what the difference will be between the sum and the known dodank. Well, for this task, we need a rule for recognizing whole numbers:
Viznachennya 1
And, in order to calculate the difference between two numbers, it is necessary to add the number that is closest to the number before changing. a – b = a + (- b), where a and b are the whole number; b ta – b – protimal numbers.
Let's take a look at the rule, then. We will prove the justice implied by the rule of equity. For this purpose, using the substitution of integer numbers, we add up to a + (- b) to raise b and convert what is removed as a result of changing a, then. Let's check the action of equality (a + (- b)) + b = a. On the base of power for adding whole numbers, we can write down the equation of equalities: (a + (- b)) + b = a + ((- b) + b) = a + 0 = a, and this will be a proof of the rule for adding whole numbers.
Let's take a look at the established rules for identifying whole numbers on specific butts.
Consider a whole positive number, apply
Butt 1It is necessary to remove the whole number 15 from the positive integer 45.
Decision
This is consistent with the rule that from the given number 15 the whole positive number 45 must be removed before the changed number 15 is added to the number 45. less than the specified 45 . Thus, the difference between the total number of whole numbers 15 and - 45 is determined. Having calculated the required sum of numbers from the preceding signs, the number is subtracted - 30. Tobto. the result of taking the number 45 from the number 15 will be the number - 30. Let's write the solution in one row: 15 - 45 = 15 + (- 45) = - 30.
Version: 15 – 45 = – 30.
Butt 2
It is necessary to remove the whole negative number - 150 from the whole positive number 25.
Decision
As a rule, add up to the changed number - 150 number - 25 (this is equal to the given 25, which appears). We know the sum of all negative numbers: - 150 + (- 25) = - 175. In such a manner, the shukana is ancient. We will write all the solutions as follows: - 150 - 25 = - 150 + (- 25) = - 175.
Version: - 150 - 25 = - 175.
Vіdnіmnya zero, butt
The rule of taking out whole numbers makes it possible to derive the principle of taking out zero from an integer - taking out zero from any integer does not change that number. a - 0 = a de a - more than a whole number.
Let me explain. Similar to the rule of substitution, the subtraction of zero is an addition to the changed number, which is proximal to zero. Zero is a number that is better than itself, that is. Raising zero is the same as adding zero. On the basis of obvious power, adding zero to any integer does not change that number. In such a manner
a - 0 = a + (- 0) = a + 0 = a.
Let's look at a simple application of identifying zero from different whole numbers. For example, the difference is 61 - 0 is equal to 61. If you subtract zero from a negative whole number - 874, then you get - 874. When you take zero from zero, you subtract zero.
Consideration of a whole negative number, apply
Butt 3It is necessary to remove from the integer 0 the negative integer - 324.
Decision
In accordance with the rule, the difference 0 - (- 324) must be added to the changed number 0, the corresponding value is - 324. Todi: 0 - (-324) = 0 + 324 = 324
Type: 0 - (- 324) = 324
Butt 4
Calculate the difference - 6 - (- 13) .
Decision
It is clearly visible from the whole negative number - 6 from the whole negative number - 13. For which we can calculate the sum of two numbers: the changed one - 6 and the number 13 (then the corresponding number appears - 13). Removable: - 6 - (- 13) = - 6 + 13 = 7.
Version: - 6 - (- 13) = 7.
Finding equal whole numbers
As soon as the tasks are changed and equal values are obtained, their difference is equal to zero, then. a - a = 0 de a - be a whole number.
Let me explain. This is similar to the rule of recognizing integers a - a = a + (- a) = 0, which means: in order to get a whole number equal to one, you need to add to a number equal to one, so that the result is zero.
For example, the difference between equal integers is 54 and - 54 equal to zero; In this case, from the number 513, the number 513 is taken off as zero; By taking away zero from zero, we also subtract zero.
Checking the result using whole numbers
Re-verification is necessary for further addition. For this reason, before removing the difference, we add the following: the result will appear as a number that is the same as the one changed.
Butt 5
The whole number was divided up - 112 from the whole number - 300, with the difference being 186. How was the day divided correctly?
Decision
We must recheck this with the above stated principle. Adding to the given difference is: - 186 + (- 112) = - 298. We subtracted the number that was changed from the given one, so a correction was made when calculating the difference.
Version: no, the video was compiled incorrectly.
Finally, let's take a look at the geometrical blurring of the whole numbers. Let's cross the horizontal coordinate line, straighten the right hand:
Most of all, we have established a rule for this work, which is consistent with the following: a - b = a + (- b), then the geometrical substitution of numbers a and b is avoided by geometric substitution of adding whole numbers a and -b. This means that to derive from an integer a an integer b it is necessary:
Destroy from the point with coordinate a to b single cuts to the left, since b is a positive number;
Destroy points at coordinate a on | b | (modulus of number b) of single sections of the right hand, since b is a leading number;
Lose at the point with coordinate a when b = 0.
Let's take a look at the example from the graphic image:
Please don't forget to add the whole number - 2 - the whole positive number 2. For this purpose, according to the above diagram, we move to the left by 2 single sections, moving, in this manner, to the point at coordinate - 4, then. - 2 - 2 = - 4.
Another example: derived from the whole number 2, the whole negative number is 3. So, according to the diagram, let’s move the right hand to | - 3 | = 3 single cuts, cutting in this order at the point with coordinate 5. Detectable jealousy: 2 - (- 3) = 5 and illustration before:
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Divided: cob school
Class: 2
Main goals:
1) formulate statements about the power of the sum taken from the number, the existence of the corresponding power for the rationalization of calculation;
2) train your mental skills, knowledge and skills for independent analysis and storage tasks;
3) show accuracy.
Demo material:
1) image of Dunno. <Рисунок1 >
2) cards with words: a – barking – success – hov.
3) sand anniversary.
4) standard sum from the number.
a-(b+c) = (a-b)-c = (a-c)-b
5) standard procedure. a – (b+c)
6) self-checking template for step 6:
7) self-verification test for the 7th stage.
1) 45 -15 = 30 (m) - lost from Denis
2) 30 - 13 = 17 (m)
Verdict: Denis lost 17 marks.
Distribution material:
1) beige color card with individual instructions for stage 2 of the skin study:
2) a green color card with individual tasks for stage 5.
3) independent robot at stage 6.
4) light signals: red, yellow, green.
Lesson heading:
I. Self-esteem before initial activity.
1) motivate to activity during the lesson through the promotion of a fairy tale character;
2) determine the appropriate framework for the lesson: take a sum from the number.
Organization of the process at stage I.
What did you repeat last lesson? (Power added)
What kind of addition did the authorities repeat? (Moved and edited)
Why do we need to know the power of addition? (Virish the butts more tightly)
Today our guest is the Kazkov hero Neznayko .<Рисунок1 >
We prepare a lot of tasks and follow what we do in class. Are you ready?
II. Updating knowledge and fixing difficulties in activity.
1) train Rozumov’s operation - Uzagalnennya;
2) repeat the rules for the order of actions in the lines with bows;
3) organize the development of individual activities and the fixation of training in the marketing industry.
Organization of the initial process at stage II.
1) Usny rakhunok.
Marvel at the doshka and sign it up. <Приложение 1 >
If we have written it correctly, then we read it as if we were encrypted by Unknown:
(Up to 27 add 19, after 46;
Z 46 vіdnyat 24 vіde 22;
To 22 add 38 to 60;
From 60 to 5 from 55)
Increase 55 by 200. (200+55=255)
Give a description of the number 255. (255 is a three-digit number that contains two hundred, five tens and five ones. The previous number is 254, the next is 256, the sum of digit additions is 200+50+5, the sum of digits is 12).
Display the number 255 in different units of the rack. (255 = 2s 5d 5od = 25d 5od = 2s 55od)
Dimensions of 255 cm in different species of vimiru. (255 = 2m 5dm 5cm = 25dm 5cm = 2m 55cm)
2) Repeating the rules for the order of actions in the lines with bows. <Приложение 2 >
How are expressions similar? (components of action, but new order of action)
What are the expressions? (Massacres)
How is the vision presented? (Apparently the sum of two numbers)
What did we repeat, knowing the meaning of the expressions? (Order of actions).
Have you ever repeated the order of actions?
Where can we repeat the rules for the order of actions? (The friend has standards <Приложение 3 > )
3) Individual assignment.
Take a pen and a sheet of beige color. <Приложение 4 >
Apply it immediately at any hour. You follow my team with your decision.
Respect! Let's start! ...
Raise your hand, who is shaking their butts?
Raise your hand, who is holding the butt?
Specify the standard that you used to align the buttstocks. (We don’t know the standard).
Who doesn't wear butts?
III.Identification of the reasons for the difficulty and setting of action.
1) identify and record the cause of the difficulty;
2) suit the topic of the lesson.
Organization of the initial process at stage III.
Repeat, what kind of misfortune was it?
Why is Vinikla skruta? (It’s not enough time, there is no subordinate power)
Why bother? (Children's leave). Place the sheets.
Try to formulate a lesson outline.
Formulate the topic for the lesson.
Lesson topic: Making money from numbers. Speak the topic of the lesson to yourself, out loud. (The topic of the lesson is written down in school)
IV. Pobudova project to get out of the twist.
1) organize a new way of acting for children, a vikory dialogue, and a conclusion;
2) record a new way of doing something significant in your language.
Organization of the initial process at stage IV.
Marvel and read the verse: 87 – (7+15).
Which supplement is better for picking up the kidney? (It’s more important to pick up first additions – 7)
We raised the first donk, but we need to raise two additional ones. What do you need to earn? (Raise another addition)
The teacher keeps a record of the school. <Приложение5 >
Marvel, I replace the number 87 with the letter a, the number 7 with the letter b, the number 15 with the letter c, and you get jealousy. <Приложение 6 >
Let's marvel. Read Viraz: 87 – (15+7)
What is the best way to remove the addition from the number 87? (It’s better to pick up another addon 7)
The teacher keeps a record of the school.
We received another addition, but we need to receive two additions. What do you need to earn? (Raise first dodanok)
The teacher keeps a record of the school. <Приложение 7 >
Let's marvel. I will replace the number 87 with the letter a, the number 7 with the letter b, the number 15 with the letter c, and you get jealousy. <Приложение 8 >
Find out how you can transfer the amount from the number. (Listen to the children’s voices)
How can we verify that we made the crowns correctly? (To the friend)
Open the handcuff on page 44. Read the rule. <Приложение 9 >
V. Primary consolidation in external promotion.
Meta: create a solution for fixing the learned method of action in the current promotion.
Organization of the process at stage V.
Who can repeat the rule?
Why is Vinikla skruta? (We couldn’t virišuvat)
Can we do it now?
What helped us? (Rule of taking a sum from a number)
Take a sheet of green color and, at my command, wash the butts. <Приложение10 >
Respect! Let's start! Stop!
Frontal preparation.
How much did the first butt cost?
Who can raise their hand like that?
Who's giving me mercy?
How much did the other butt cost?
Who can raise their hand like that?
Who's giving me mercy?
How did you virishuv? Where is the pardon? What is the reason?
Can you tell me that you have learned to virishuvat? (So)
What helped? (We know the rule, the liquidity of the decision has increased)
Where can we zastosuvati new reception? (When the order is high, apply).
At home, turn off on page 44, building No. 4, on the new rule. Think about writing down your butt. (Zavdannya is written in doshtsi). <Приложение11 >
Who guesses the rule?
VI. Independent work through self-verification.
1) organize independent testing of standard tasks by students in a new way of doing things through self-testing lesson after lesson;
2) organize children’s self-assessment of the correctness of their knowledge.
Organization of the process at stage VI.
And now Dunno will marvel at how we have learned to implement the new rule.
Independent robot. <Приложение12 >
Are we moving towards an independent robot? (Understand difficulties and overcome them, test your strengths)
What are the ways to extract money from the number? (It’s easy to pick up one additional item and then another)
Take a white-colored arkush. They are starting to follow my team.
Let's start... Stop.
Take a simple olive and remove it from the glass. <Приложение13 >
For those who have this, put “+”.
Whoever has a pardon, put “-”.
Raise your hand, who got it all?
Raise your hand, who has mercy? De vinikla skruta? (Counting technique)
You did a wonderful job.
What did you learn in class? (learned how to manually subtract a sum from a number)
Earn money. (Types of children)
Fizminutka.
VII. Turning on until the system knows and repeats.
Meta: repeat the task, find a manual way to solve it.
Organization of the initial process at stage VII.
Where can you set the following rules? (When the order is high, apply)
Marvel and read book No. 3 to yourself.
Conduct a plant analysis. (The problem shows that Denis gave 45 marks. He gave Petya 15 marks, and Kolya gave 13 marks. We need to find out how many marks he has lost.
To answer the question, you need to collect the number of stamps that Denis gave to Petya and Kolya. We can’t immediately respond to this request, because we don’t know how many stamps Denis gave to Petya and Kolya. And we can find out that we have given a number of stamps, as we have given to Petya, up to a number of marks, as we have given to Kolya).
In case of analysis, the teacher supplements with nutrition, as presented below:
What does the boss know?
What do you need to know?
How do I report on the requested task?
Can we immediately inform you about the supply? Why?
How can we find out? Yak?
Show the plan for solving the task. (The first step is to find out how many stamps Denis gave, then we will answer the question). <Приложение 14 >
Who views the task differently? (To inform you about the question, you need to collect the number of stamps that Denis gave to Petya, and then the number of stamps that he gave to Kolya)
Describe the plan for solving the problem in another way. (First we find out how many stamps Denis lost after he gave Petya wine, and then we find out how many stamps he lost after he gave Kolya 13 stamps and types Imo to the power supply). <Приложение15 >
What is the most powerful way to resolve the task? Why? (For others, it’s easier to lift one part, and then another part)
Write down the solution to the problem manually. Self-verification for the lesson. <Приложение16 >
VIII. Reflection of activity.
1) record a new way of learning in class: take a sum from the number;
2) fix the difficulties that have been lost, and ways to fix them;
3) evaluate your activity during the lesson, please your homework.
Organization of the initial process at stage VIII.
Well, today in class another rule was brought to our knowledge, guess it. (Today in class we learned how to subtract a sum from a number. To subtract a sum from a number, you can first subtract one addition and then another)
Who's having troubles?
How did you manage to hem them? Yak?
What else do you need to work on?
Teacher grades for work in class.
Home decoration: page 44 No. 4. Come up with and spin your butt on a new topic.
Literature
1) Handbook "Mathematics 2nd grade, 2nd part"; L.G. Peterson. Exhibition "Yuventa", 2008
3) L.G. Peterson, I.G. Lipatnikova "Usni right in mathematics lessons 2nd grade." M.: "School 2000..."
vidnіmannya), return addition. Place a minus “−” after the additional symbol. This is the case, for the help of which, for the bag and one of the dodanks, you can find another dodanok.The number from which is seen, called zmenshuvane, and the number that appears is rises. The pouch for daily use is called retail.
Let us know: the sum of 2 numbers cі b one a Well, the sacristan a−c will b, and the difference a−b will c.
It is easiest to work with the “stacked” method.
The table is taken into account.
To make it easier and quicker to master the learning process, look at and memorize the learning table up to ten for grade 2:
The power of natural numbers.
- Obviously, as a process, there is no shifting power: a−b≠b−a.
- The difference between these numbers is equal to zero: a−a=0.
- Calculation of the sum of 2 whole numbers from a whole number: a−(b+c)=(a−b)−c.
- Divide a number from the sum of 2 numbers: (a+b)-c=(a-c)+b=a+(b-c).
- The power of the rebels is multiplying more and more: a·(b−c)=a·b−a·c and (a−b)·c=a·c−b·c.
- And all other authorities recognize whole numbers (natural numbers).
Let's take a look at some of them:
The power of two equal natural numbers.
The difference between two natural numbers is equal to zero.
a−a=0,
de a- Whether the number is natural.
The observation of natural numbers does NOT have any shifting power.
In addition to the described power, it is clear that from two natural numbers, the moving power is working. In all other options (which change ≠ appear), the expression of natural numbers does not have any displacement power. Or, to put it another way, what changes and rises does not change in places.
If the changes are more obvious and we decided to change them in their places, it means that we can understand from a natural number, which is less, a natural number, which is greater. This system reflects the essence of natural numbers.
Yakshcho aі b unequal natural numbers, then a−b≠b−a. For example, 45-21≠21-45.
The power of the sum of two numbers from a natural number.
From the designated natural number, remove the required sum of 2 natural numbers - the same as from the designated natural number, remove the 1st addition of the required amount, and then, from the covered sum, raise the 2nd addition.
For additional letters, you can express it in the following order:
a−(b+c)=(a−b)−c,
de a, bі c- natural numbers, obligatorily guilty of contorting one’s mind a>b+c or else a=b+c.
The power of extracting a natural number from the sum of two numbers.
Subtract a natural number from the sum of 2 numbers - the same number that you subtract from one of the additions, and then add up the difference and other additions. The number that appears cannot be greater than the addition from which the number is displayed.
Let's go a, bі c- natural numbers. This means that a larger or more ancient c, jealousy (a+b)−c=(a−c)+b will convey the truth, and b larger or more ancient c, That: (a+b)-c=a+(b-c). Koli i aі b larger or more ancient c, which means that the remaining jealousies are in the same place, and they can be written like this:
(a+b)-c=(a-c)+b=a+(b-c).
The concept is best seen from the butt. You decided to drink tea from the tsukkerki. The vase had 10 tsukerki. You took 3 tsukerki. How many tsukerki has the vase lost? If we notice 3 in 10, then the vase will lose 7 tsukerki. Let's write it down mathematically:
Let's take a look at the record:
10 – this is the number we take, or if we change it, we call it change.
3 is the number we see. They call him yogo rises.
7 – this number is the result of the above or else called sacristy. The difference shows how much the first number (10) is greater than the other number (3) or how much the other number (3) is less than the first number (10).
If you doubt that you have correctly found the difference, you need to work out re-verification. Before the end of the day, add another number: 7+3=10
When you change it, it will not appear less.
Let us summarize from what has been said. Vіdnіmannya- this is the case, for the help of one of the dodanks, there is another dodanok for the bag.
The letter looks like this:
a-b =c
a – zmenshuvane,
b - rises,
c – difference.
The authorities withdraw money from the number.
13 — (3 + 4)=13 — 7=6
13 — 3 — 4 = 10 — 4=6
The stock can be modified in two ways. The first way is to know the sum of the numbers (3+4), and then remove the original number (13). Another way is to select the first addition (3) from the leading number (13), and then, with the difference removed, select another addition (4).
The literary view of power is derived from the number as follows:
a - (b + c) = a - b - c
The power of extracting numbers from the sum.
(7 + 3) — 2 = 10 — 2 = 8
7 + (3 — 2) = 7 + 1 = 8
(7 — 2) + 3 = 5 + 3 = 8
To add a number to a sum, you can subtract that number as one addition, and then add another addition until the difference is reached. There will be more awareness of the addition.
The letter looks like this:
(7 + 3) — 2 = 7 + (3 — 2)
(a +b) -c=a + (b - c), for the mind b > c
(7 + 3) — 2=(7 — 2) + 3
(a + b) - c = (a - c) + b, for mind a > c
Power comes from zero.
10 — 0 = 10
a - 0 = a
How to raise zero those will be the same number.
10 — 10 = 0
a-a = 0
How to pick up the same number instead of a number then it will be zero.
Meals on the topic:
In the case of 35 - 22 = 13, name the changes, and there is a difference.
Type: 35 – change, 22 – change, 13 – difference.
Since the numbers are the same, why is their difference different?
Version: zero.
Do you need to check the date 24 - 16 = 8?
Version: 16 + 8 = 24
Table of natural numbers from 1 to 10.
Apply to problems on the topic “Discovery of natural numbers.”
Example #1:
Fill in the missing number: a) 20 - ... = 20 b) 14 - ... + 5 = 14
Type: a) 0 b) 5
Example #2:
You can select the following: a) 0 - 3 b) 56 - 12 c) 3 - 0 d) 576 - 576 d) 8732 - 8734
Version: a) neither b) 56 - 12 = 44 c) 3 - 0 = 3 d) 576 - 576 = 0 e) nor
Butt #3:
Read Viraz: 20 - 8
Proverb: “By twenty we will raise everything” or “by twenty we will raise everything.” Use the words correctly
A variety of unknown numbers and ib the number of elements in the additional multiplier B to the multiplier A is called for the reason thatn(A)= a, n(B)= b, B.A., then. A -b = n(A B). It is clear that A = B (AB), then.n(A)= n(B) + n(A B).
Let's get this across. Bo behind the sink U- the power of impersonality A, then they can be served as in Fig. 3.
The discovery of natural (entirely invisible) numbers is designated as an operation returning to the warehouse: A -b = c () b + c = a.
Retail AB This little one is shaded. Bachimo, scho multiply Uі AB don’t pretend that they are one thing A. Therefore, there are many elements in the multiplicity A can be found by the formula n(A)=n(B) + n(AB), information from the designated operation, return data, can be removed n(AB) = A -b.
A similar dimness is removed by the removal of zero, as well as by the A h A. So yak A = A, AA =, That A - 0= aі a - a = 0.
Retail A -b There are a lot of unknown numbers and then, if .
Action, for help in knowing the difference A -b, called vidnіmannyam, number A- change, b- rises.
Let us show that 8 – 5 = 3 . Let us give two multipliers such that n(A) = 8, n(B) = 5. І let go of the impersonal U is a subset of impersonality A. For example, A ={a, s, d, f, g, h, j, k} , B={a, s, d, f, g} .
We know additional impersonality U to multiply A: AB ={h, j, k). Let's say that n(AB) = 3.
Otje , 8 - 5 = 3.
The interconnection of the different numbers and the different multiplicities allows you to select actions for the most common text problems. It is clear why the present situation is based on a special observation, and to unravel it: “There were 7 trees growing near the school, 3 of them were birches, and the other were lindens. How many linden trees grew near the school?
The plant is visible, representing a leather tree, planted in a circle around the school (Fig. 4). Among them there are 3 birch trees - their hatching is visible to the little one. There are also trees - unshaded circles - and linden trees. That is, their insoles, as many as 7 will be raised 3 , then . 4.
The problem has three parts: impersonal A of all trees, without personality U- birch, which is a subset A, and impersonal Z lip - here and additional impersonality U before A. The problem requires knowing how many elements there are in a given supplement.
Behind the washroom n(A) = 7, n(B)= 3 i BA. Let's go A ={a, b, c, d, e, f, g} , B={a, b, c} . We know additional impersonality A before U: AB ={d, e, f, g)і n(AB) = 4.
To mean, n(C) = n(AB) = n(A)- n(B)= 7 - 3 = 4.
Well, there were 4 linden trees growing near the school.
The considered approach to the addition and identification of entire unknown numbers allows one to understand different rules from multiplicity theoretic positions.
The rule for extracting a number from the sum: To subtract a number from the sum, it is sufficient to subtract the number from one of the additions and add another addition to the final result. at ac maєmo, sho (a+b)-c=(a-c)+b; at bc maєmo, sho (a+b)-c=a+(b-c); at acі bc You can vikorystuvati be-yak with the given formulas.
It's clear that this rule is: Don't A, B, C- such multiplicities that n(A)=a, n(B)=bі AB= , SA(Fig.5).
It doesn’t matter if you call Euler for help, because for many people there is a place for jealousy.
The right side of equality looks like this:
The left part of jealousy looks like: Ozhe (a + b) - c = (a- c) + b,at think about it a>c.
Rule for taking money from a number : To add up to a number of numbers, you need to add up to that number one by one, then. what the hell a b +c, maєmo A - (b + c) = (a – b) – c.
It is clear that this rule has changed. For these many people, jealousy has its place.
Then we deny that the right part of the jealousy may look like this: The left side of jealousy looks like: .
Otje (a + b) - c = (a- c) + b, at think about it a>c.
Rule for determining the difference from numbers:
to subtract from the number A retail b - c, it is enough to add a notice until this date h and change the results obtained b; at a>b can be removed from the number a changed b i until the result is calculated and added to the result. A - (b - c) = (a + c) - b = (a - b) + c.
To mean, A(BC) = .
Otje, n(A(BC)) = n( ) і A - (b - c) = (a + c) - b.
The rule for selecting numbers from the difference: to take the third number from the difference of two numbers, Dosit to change the sum of two other numbers, then. (A -b) - c = a - (b + c). The calculation is similar to the rule for taking a sum from a number.
butt. In what ways can you find out the difference: a) 15 – (5 + 6); b) (12 + 6) – 2?
Decision. a) Vikorist’s rule for taking the sum from a number: 15 – (5 + 6) = (15 – 5) – 6 = 10 – 6 = 4.
Abo 15 - (5 + 6) = (15 - 6) - 5 = 9 - 4 = 4.
Abo 15 - (5 + 6) = 15 - 11 = 4 .
b) Vikorist’s rule for deriving numbers from the sum: (12 + 6) - 2 = (12 - 2) + 6 = 10 + 6 = 16.
Abo (12 + 6) - 2 = 12 + (6 - 2) = 12 + 4 = 16 .
Abo (12 + 6) – 2 = 18 – 2 = 16.
These rules allow simple calculations and are widely followed in elementary mathematics courses.
Vantaged...