Something About “Pi” ( ∏ )

Pi ( ∏ ) is the most famous irrational number. Pi or ∏ actually denotes the ratio of the circumference of a circle to is diameter. It was proved to be an irrational number by Lombart in 1767. Using the method of infinite series, William Shanks in 1873 computed the value of Pi to 707 decimal places. Succeeding works were completed in 1948 by the Englishman D. F. Fergusson and the American J. W. Wrench Jr. . They corrected te work of Shanks and carried the computation to 808 places.

Recently, electronic calculators have computed the value of Pi to thousands of places,To twenty decimal places,

∏ = 3.14159265358979323846……….

The dot implies that Pi is an infinite decimal and an irrational number. Irrational numbers are infinite, non-repeating decimals. They may be expressed approximately to any required number of decimal places. To five places, ∏ = 3.14159. That is the terminating decimal 3.14159, as well as the familiar 22/7 or 3 1/7 are rational numbers that are approximations to the value of Pi.

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