Within a circle, the ratio of the diameter of a circle to its circumference is called PI Pay attention to the questions. I used to type X on the test paper, but many people check √, so I want to have a look My understanding: "the ratio of the diameter of a circle to the circumference of a circle" is wrong. It should be "the circumference of a circle and the diameter of a circle"! Thank you for helping me to answer the friend!

When the circumference of a circle is fixed, its diameter is inversely proportional to its PI______ (judge right or wrong)

Because the PI is a fixed number and cannot change with the change of the diameter of the circle, the diameter of the circle is not proportional to the PI;
So the answer is: wrong

What is the ratio of the Pi of a circle with a diameter of 15 cm to that of a circle with a diameter of one meter

Is the ratio of pi to PI
After simplification, it is 1:1

100 bits after PI, and 1 to 20 cm in diameter, as soon as possible

Thank you, but do you have any area of 1 to 20 cm in diameter

Judgment: the ratio of circumference to diameter is the ratio of circumference to diameter PI is the ratio of circumference to diameter. Is that right PI is the ratio of circumference to diameter, right

yes.

The Pi of a large circle is greater than that of a small circle______ (judge right or wrong)

According to the definition of PI, PI is the ratio of circumference to diameter of a circle. It is a constant and constant. Therefore, the Pi of large circle and small circle is not distinguished
So the answer is: ×

Is it true or false that the circumference of a circle must be times the circumference of its diameter This is our sixth grade examination question. I don't think he said it was in the same garden, so I typed it wrong, but my question was wrong

A: that's right
Because the circumference of the circle L = π D (D is the diameter of the circle)
This sentence is in the same circle by default

About Years ago, ancient mathematicians in China were the most accurate in calculating the value of π .

About 1500 years ago, Zu Chongzhi, an ancient Chinese mathematician, was the most accurate one to calculate the value of π
So the answer is: 1500, Zu Chongzhi

How many bits of PI have been calculated?

Recently, a Japanese man has just set a new record of accurate pi to 5 trillion decimal places. A researcher at Yahoo has used "cloud computing" technology to get pi to 2000 trillion decimal places
A researcher at Yahoo technologies uses "cloud computing" technology, using 1000 computers to calculate the PI at the same time for 23 days. During this period, each computer has to run different formulas to decompose the complex formula of PI into smaller mathematical problems, and then combine them together to get the precise value of PI, Szer's calculation is equivalent to 500 years of work on a computer
This news is on the 27th of September

What is the PI calculated

In a circle with radius r, make an inscribed regular hexagon. In this case, the side length of the regular hexagon is equal to the radius r of the circle. Therefore, the circumference of the regular hexagon is equal to 6R. If the circumference of the inscribed regular hexagon is regarded as the approximate value of the circumference of the circle, and then the ratio of the circumference of the inscribed regular hexagon to the diameter of the circle is regarded as the ratio of the circumference of the circle to the diameter of the circle, Obviously, this is not accurate
We have a method to calculate the approximate value of PI
As early as 1700 years ago, Liu Hui, an ancient mathematician in China, used the cyclotomy to calculate the Pi of 3.141024. After Liu Hui, the ancient Chinese mathematician Zu Chongzhi made important progress in the research of calculating pi. His results obtained two numbers: one is surplus (the approximate value of surplus), which is 3.1415927; the other is (n ǜ) number (the insufficient approximation), The true value of PI is 3.1415926. The true value of PI is just between the two surplus numbers. Zu Chongzhi also uses two fractional values: one is 22 / 7 (about 3.14), which is called "approximate rate"; the other is 355 / 113 (about 3.1415929), which is called "density ratio". The density ratio obtained by Zu Chongzhi is at least 1000 years earlier than that obtained by foreign mathematicians
⑴ 2∕π＝√2∕2*√（2＋√2）∕2*√（2＋√（2＋√2））∕2……
⑵ π∕2＝2*2*4*4*6*6*8*8…… ∕（1*3*3*3*4*5*5*7*7……）
(3) π / 4 = 4arctg (1 / 5) - arctg (1 / 239) (Note: TGX =...)
⑷ π＝426880√10005∕（∑(（6n）!*（545140134n+13591409))
∕（（n!）*（3n)!*（-640320）＾（3n)))
（0≤n→∞）
Modern mathematicians usually use this formula to calculate pi, which is beyond the reach of ordinary people
And the use of the formula of Chinese Pi is much simpler, ordinary middle school students can use the conventional calculation tools to reference: The Complete Book of junior high school theorem