Bài Giảng: Số nguyên tố

This video is about the 17th lesson of the 10th element in the 1st lesson of the 1st lesson of the 1st lesson. To begin the lesson, this is the following situation. Mom bought a bunch of flowers, which are 11 roses. Mai helps Mom transfer these flowers to small jars. She mixes the flowers in each jar. You can see that you can't put all the flowers in the flower pots Each flower pot must have more than one flower Even if the number of flower pots is 2, 3, 4 or 5 But if you put one flower pot and 10 flower pots You can put all the flowers in 2 pots Each pot has 5 flower pots So, what is the difference between number 11 and number 10? What is the difference between number 11 and number 10? And what does this have to do with the number of flower pots? We can see that number 11 has 2 ways to put the flowers in Number 11 puts the flowers in 1 flower pot Because 11 divided by 1 Number 11 puts the flowers in 11 flower pots Because 11 divided by 11 We can see that 11 flowers have 2 mixing windows 11 flowers have 4 ways to place flowers in 10 flowers in 1 flower pot Because 10 divided by 1 10 flowers in 2 flower pots Because 10 divided by 2 10 flowers in 5 flower pots Because 10 divided by 5 10 flowers in 10 flower pots because 10 died for 10, we realize that 10 has more than 2 wishes, and specifically, this is a 4-wish. So, with numbers that only have 2 wishes, 1 is it, and with numbers that have more than 2 wishes, is there any difference? Let's find out the content of Lesson 10. NUMBER OF ELEMENTS 1. NUMBER OF ELEMENTS AND NUMBERS Step 1. I ask you to think and answer the question. A. Does number 0 die for 2, 5, 7, 2017, 2018? Do you have any comments on the number of wishes of 0? B. How many wishes does number 1 have? Your time to think begins. Step 1. I ask you to think and answer the question. A. Does number 0 die for 2, 5, 7, 2017, 2018? Does number 0 have any wishes? B. Does number 1 have only 1 wish? So, what is the number of wishes of numbers greater than 2? Let's divide the numbers in version 2.1 into 2 groups. The groups with numbers only have 2 wishes, and the groups with numbers have more than 2 wishes. Here are also the numbers 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11. We can easily see that the numbers only have 2 wishes, including numbers 2, 3, 5, 7, and 11. The numbers with more than 2 wishes are numbers 4, 6, 8, 9, and 10. And then people call the numbers 2, 3, 5, 7, 11 as the number of elements. And the numbers 4, 6, 8, 9, and 10 are the groups of numbers. So, can you tell me which numbers are called the number of elements? And which numbers can we easily see? The number of elements is the number of natural numbers greater than 1. There are only 2 wishes, which are 1 and it. And the number of elements is the number of natural numbers greater than 1. And there must be more than 2 wishes. So, if a natural number is not the number of elements, then it must be the number of elements. Let's find that number. Here is the number of elements table. Let's observe the number of elements table and let us know which number is the smallest. From the number of elements table, I can easily see that the smallest element is number 2 and is the only integer element. In this part, you need to pay attention. The numbers 0 and 1 are not the number of elements and are not integers. Number 2 is the smallest number and is the only integer element. From the knowledge just acquired, please make her practice 1. Please find a suitable house for the numbers in table 2.1. 1. Based on the concept of determining the number of elements and the number box, I can easily recognize the numbers 2, 3, 5, 7, 11 will be arranged in the house of the number of elements. And the numbers 4, 6, 8, 9, 10 will be arranged in the house. Next, I have an example 1 to help you practice how to identify the number of elements and the number box. Example 1. Which number below is the number of elements? Which number is the number box? Let me know why. A. 1975 B. 17 We see that the number 1975 is divisible by 5. In addition to the two wishes of 1 and 1975, it also has the wish of 5. So the number 1975 is the number box. B. Number 17 only has two wishes of 1 and 17, so 17 is the number of elements. Through this example, I notice that to determine a number is a number box, we often use divisible symbols to find another wish 1 and it is. So I have guided you to learn about the number of elements and the number box. Go home and practice more exercises. Strengthen the knowledge of the number of elements and the number box. Examples, explanations, where is the number of elements, where is the number box. Prove that 1 is the number box.