Usage: add and subtract to find the initial value and final value of the product. For example, you can write "i= 1" under the symbol and "n" above the symbol, which means that I in the following quadrature formula is added to n from 1. That is, (1+d1/p1) (1+d2/p2) ... (1+dn/pn).

In mathematics, pi is often mentioned. Pi, generally expressed by π, is a common mathematical constant in mathematics and physics. It is defined as the ratio of the circumference to the diameter of a circle. In the analysis, π can be strictly defined as the smallest positive real number x satisfying sin(x) = 0.

characteristic

It is of little practical significance to calculate the value of pi so accurately. A dozen pi values used in modern science and technology are enough. If the Hubble volume is calculated by using the 39-bit precision pi value, the error is less than the volume of an atom. In the past, people calculated pi to explore whether pi circulated decimals. Since Lambert proved that pi is irrational in 176 1 and Lin Deman proved that pi is transcendental in 1882, the mystery of pi has been uncovered.

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