# The Secret of Number 9

There are interesting and mysterious events in mathematics. These are sometimes the image of objects, sometimes the life of a mathematician or the quirk of any number. Although the interesting features of numbers in mathematics are sometimes the work of a mathematician, the interesting features of the number 9 that we will explain bring to mind the questions of who and when it was made.

The oldest place in number 9 is found in Greek mythology. While the mythological god we call “9Mus” is described as the goddess of art, the number 9 in Norwegian Mythology is the number of the most important features of man. Wisdom, mightiness, effort…. For us, the expression “You are 9 alive like a cat” is used for people who are lucky. So what does this figure mean to us mathematically? ALSO SEE: Why Car Windows are not Shattered?

The number 9 has a characteristic feature in our number system. When we add up the numbers that preceded it,

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 = 36

It will give the number 36, and once we add the numbers in the number 36, it will be 3 + 6 = 9. Also, if all the numbers in our number system are added, that is, add 9 to the sum above,

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 = 45

When the numbers of 45 are added up again, the number 4 + 5 = 9 will be obtained. When the number 9 is multiplied by any number, weird things come up again.

1 x 9 = 9

2 x 9 = 18 (1+ 8 = 9)

3 x 9 = 27 (2+ 7 = 9)

4 x 9 = 36 (3 + 6 = 9)

5 x 9 = 45 (4 + 5 = 9)

6 x 9 = 54 (5 + 4 = 9)

7 x 9 = 63 (6 + 3 = 9)

8 x 9 = 72 (7+ 2 = 9)

9 x 9 = 81 (8 + 1 = 9)

These simple multiplicative processes we gave above are actually a reflection of a historical process. Especially in excavations carried out in Egypt, there are processes in this kind of interesting clay tablet. One of them is as follows;

9 x 9 x 9 = 729 (7 + 2 + 9 = 18 = 1 + 8 = 9)

9 x 9 x 9 x 9 = 6561 (6 + 5 + 6 + 1 = 18 = 1 + 8 = 9)

9 x 9 x 9 x 9 x 9 = 59049 (5 + 9 + 0 + 4 + 9 = 27 = 2 + 7 = 9)

9 x 9 x 9 x 9 x 9 x 9 = 531441 (5 + 3 + 1 + 4 + 4 + 1 = 18 = 1 + 8 = 9)

Can you see the elegance above? B.C. It is an interesting information obtained by multiplying the above 9 numbers, which are said to be from the 3000s, by the product of 3, 4 and 5 times… It was a really impressive work considering those times.

The number 9!

Well, let’s play a game like this. Choose a number with 9 digits, all of the same number, and 9 in total. You immediately found that this number is only 111, 111, 111. So far, everything is fine. Now take this number and multiply by itself. You will see a number exactly like this.

111, 111, 111 x 111, 111, 111 = 12345678987654321

Although it does not seem like a nice appearance, when we look into the number a little more, in fact, the number above has gathered around the number 9 from the left and right. This number is referred to as “Golden Number” in mathematics. (Do not confuse with the ratio of gold) Also, when you add the number from the product above,

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1 = 81 = 8 + 1 = 9

It will be. Now let’s try to make a multiplication table like this. Note the holistic beauty that will occur when we multiply the multiples of the number 9 of 12345679, which we take under the name of both a paradox and mathematical aesthetics.

12345679 x 1 x 9 = 111, 111, 111

12345679 x 2 x 9 = 222, 222, 222

12345679 x 3 x 9 = 333, 333, 333

12345679 x 4 x 9 = 444, 444, 444

12345679 x 5 x 9 = 555, 555, 555

12345679 x 6 x 9 = 666, 666, 666

12345679 x 7 x 9 = 777, 777, 777

12345679 x 8 x 9 = 888, 888, 888

12345679 x 9 x 9 = 999, 999, 999

After the above beauty, I want to ask the reader a question like this. The number 8 mentioned above, which is not available for the number, has been removed, and the strange thing is that the number 12345679 is an 8-digit number. What could be the reason we did this way? In which case can the paradox expression come out? The answer to this question is not difficult and requires some thinking. This interesting aspect of the number 9 drags a person who is passionate about mathematics. It is among the information that comes to our ears that there are more different and pleasing studies about this issue in recent years.