How to memorize the ninety nine multiplication table

The multiplication formula table is a simple multiplication table that starts from "one by one to get one" and ends with "ninety-nine eighty-one", which is derived from the multiplication formula and is convenient for multiplication calculation.

Vertical back: For example, ,—— gets one, one or two gets two, and then recite it until it gets nineteen, then it gets four for two and two, and then it gets six for two, until it reaches twenty-ninety-eight, then it gets nine for three-three, and it gets three-forty-two, until it reaches three-nine-twenty-seven, and so on, and then it is four hundred and forty-six, five and twenty-five, six and sixty-six, seven and seventy-nine, and seventy-seventy-nine, and finally ninety-nine-eighty-one.

Horizontal back: For example, the first horizontal line, one sentence one by one; the second is two sentences, one two gets two, two two gets four; And so on, the first few lines are a few sentences, and the last nine sentences go from nineteen to ninety-nine eighty-one. There is also a rule in this method, the first few lines, the next sentence is a few more than the previous sentence.

If you discover and memorize the features, it is easy to memorize the structure of the entire table in your mind and deepen your image memory.

1. The multiplication formula table is also called the "ninety-nine multiplication formula table", as the name suggests, this table is composed of nine rows and nine columns. Moreover, the whole mantra table resembles a staircase shape.

2. When reciting the multiplication formula, you should recite it line by line, and the first word at the beginning of each line must start with "one", a total of nine lines, and each line begins with "one". In this way, you won't be confused when reciting.

3. It should also be noted that the first formula of each column is related to the row in which it is located. What I just said is that the first word in each column starts with "one", and the second word is the number of lines it is in, just look at the position of the box as shown in the figure. Pass.

The two characteristics of two and three can easily remember the first formula in each line.

4. When reciting the multiplication formula, the last formula at the end of each line is the formula obtained by multiplying the same number, for example, if you memorize to the third line, you must multiply three by three as the last formula, and when you memorize the fifth line, you should multiply five by five as the end of the line. Knowing the end of each line, you immediately reflect the beginning of the downward movement.

5. Discovered such a rule, that is, horizontally, the second word of each line is the same, for example, in the second line, all the second words are "two", and in the fourth line, all the second words are "four", so it will be easier to remember.

6. You will also find a rule, that is, the number of each column, the number of differences from top to bottom, is exactly the number of columns where the column formula is located, for example, in the first column, from top to bottom in order +1, in the third column, from top to bottom in order +3, mastering this law is more helpful for memorization and memory.

The multiplication formula table starts from "one by one to get one" and ends with "ninety-nine eighty-one", which originates from the simple multiplication table that is not imitated next to the multiplication formula and is convenient for multiplication calculation.

Vertical back: For example, ,—— gets one, one or two gets two, and then recite it until it gets nineteen, then it gets four for two and two, and then it gets six for two, until it reaches twenty-ninety-eight, then it gets nine for three-three, and it gets three-forty-two, until it reaches three-nine-twenty-seven, and so on, and then it is four hundred and forty-six, five and twenty-five, six and sixty-six, seven and seventy-nine, and seventy-seventy-nine, and finally ninety-nine-eighty-one.

Horizontal transport on the back: for example, the first horizontal line, one sentence one by one; the second is two sentences, one two gets two, two two gets four; And so on, the first few lines are a few sentences, and the last nine sentences go from nineteen to ninety-nine eighty-one. There is also a rule in this method, the first few lines of the big ant, the latter sentence will increase a few times than the previous sentence.

Then, put the squares on the right side and arrange them, and all that's left is to find a way to put 24 below 18, and you're basically going to solve the problem. Then put the 24 to the left of the order in order, and you're basically done.

For the first row, move them one by one to the target position, this step requires no skill, just move the three numbers - one by one, and leave the other numbers alone. When moving the number 4, first move to the target position, move the two numbers on the left side of the 4 in the same row to the right to the right, and then move the three numbers in the first row to the left one square backwards.

At this time, you can move the 4 to the target position in the upper right corner, and remove the irrelevant number on the left side of the 4 after moving, and reverse the whole clockwise to the right by one square, so that the first row is right. The second row is the same as the first row.

Ninety-nine multiplication tables and formulas: multiplication tables.

Extended Materials. 1. Introduction.

The multiplication formula is the basic calculation rule for multiplication imitation of Hui car, division, and square in ancient Chinese calculations, and has been used for more than 2,000 years. The ancient multiplication mantra was top-down, from"Ninety-nine-eighty-one"Start, to"One and the same"止, in reverse order of what is now used, so the ancients began with the two words of the multiplication formula"Ninety-nine"As the name of this formula, it is also known as the ninety-nine table, the ninety-nine song, the nine-nine cause song, and the ninety-nine multiplication table.

2. Ancient multiplication table.

Ancient Greece, ancient Egypt, ancient India, and ancient Rome did not have a carry system, and in principle an infinitely large multiplication table was required, so it was impossible to have a ninety-nine table. For example, the Greek multiplication table must list 7*8, 70*8, 700*8, 700*8, 7,000*8, ....... In contrast, since the ninety-nine table is based on the decimal system, 7*8=56,70*8=560,700*8=5,600, 7,000*8=56,000, only 7*8=56 is required.

3. Ancient China.

In the Spring and Autumn Period and the Warring States Period, not only the decimal system was invented, but also the ninety-nine table was invented. Later, it was introduced to Goryeo and Japan in the east, and spread to India and Persia in the west through the Silk Road. The decimal system and the ninety-nine table are an important contribution of ancient China to world culture.

Today, countries around the world rarely use multiplication methods such as Greece.

First row: 1 (1 1 = 1) 2 (1 2 = 2) 3 (1 3 = 3) 4 (1 4 = 4) 5 (1 5 = 5) 6, 7, 8, 9

Second row: 2 (2 1 = 2) 4 (2 2 = 4) 6 (2 3 = 6) 8 (2 4 = 8) 10 (2 5 = 10) 12, 14, 16, 18

Third row 3, 6, 9, 12, 15, 18, 21, 24, 27

Fourth row 4, 8, 12, 16, 20, 24, 28, 32, 36

Fifth row 5, 10, 15, 20, 25, 30, 35, 40, 45

6 in the sixth row, 12, 18, 24, 30, 36, 42, 48, 54

7th row: 7, 14, 21, 28, 35, 42, 49, 56, 63

Eighth row 8, 16, 24, 32, 40, 48, 56, 64, 72

Ninth row: 9, 18, 27, 36, 45, 54, 63, 72, 81

Look at the order, it's multiplication.

Relevant mathematical knowledge.

In arithmetic, the result of multiplying two or more numbers is called their product or product. When the multiplied number is real or complex, the order of multiplication has no effect on the product, which is called commutativity. When multiplying a quaternion or matrix, or some element of a good algebraic structure, the order has an effect on the product as a result.

This shows that there is no commutative multiplication of these objects.

When there are more than two multiplied objects, a multiplication sign (uppercase ) is often used. It's like the addition of multiple objects is used as a symbol. It is generally agreed that when there is only one object of multiplication, the product is the object itself; When there are no multiplicative objects, it is also possible to agree that the so-called "empty product" is 1.