ℼ U+213C Unicode文字
Unicode
U+213C
ℼ
数値文字参照
ℼ ℼ
URLエンコード(UTF-8)
%E2%84%BC
ユニコード名
DOUBLE-STRUCK SMALL PI
一般カテゴリ－
Letter, Lowercase（文字，小文字）
Base64エンコード : 4oS8
「ℼ」に似ている意味の文字
ℼの説明
The number π (; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although fractions such as
22
7
{\displaystyle {\tfrac {22}{7}}}
are commonly used to approximate it. Consequently, its decimal representation never ends, nor enters a permanently repeating pattern. It is a transcendental number, meaning that it cannot be a solution of an equation involving only sums, products, powers, and integers. The transcendence of π implies that it is impossible to solve the ancient challenge of squaring the circle with a compass and straightedge. The decimal digits of π appear to be randomly distributed, but no proof of this conjecture has been found.
For thousands of years, mathematicians have attempted to extend their understanding of π, sometimes by computing its value to a high degree of accuracy. Ancient civilizations, including the Egyptians and Babylonians, required fairly accurate approximations of π for practical computations. Around 250 BC, the Greek mathematician Archimedes created an algorithm to approximate π with arbitrary accuracy. In the 5th century AD, Chinese mathematicians approximated π to seven digits, while Indian mathematicians made a five-digit approximation, both using geometrical techniques. The first computational formula for π, based on infinite series, was discovered a millennium later. The earliest known use of the Greek letter π to represent the ratio of a circle's circumference to its diameter was by the Welsh mathematician William Jones in 1706.The invention of calculus soon led to the calculation of hundreds of digits of π, enough for all practical scientific computations. Nevertheless, in the 20th and 21st centuries, mathematicians and computer scientists have pursued new approaches that, when combined with increasing computational power, extended the decimal representation of π to many trillions of digits. These computations are motivated by the development of efficient algorithms to calculate numeric series, as well as the human quest to break records. The extensive computations involved have also been used to test supercomputers.
Because its definition relates to the circle, π is found in many formulae in trigonometry and geometry, especially those concerning circles, ellipses and spheres. It is also found in formulae from other topics in science, such as cosmology, fractals, thermodynamics, mechanics, and electromagnetism. In modern mathematical analysis, it is often instead defined without any reference to geometry; therefore, it also appears in areas having little to do with geometry, such as number theory and statistics. The ubiquity of π makes it one of the most widely known mathematical constants inside and outside of science. Several books devoted to π have been published, and record-setting calculations of the digits of π often result in news headlines.[出典:Wikipedia]
ℼの文字を使った例文
ℼを使った文章です。 先日、森の中を散歩していたらℼの形をした妙なキノコを見つけました。そのキノコは、ヘアリーキノコの一種だそうで、名前はℼベロウドスモーキーキノコと言います。私はキノコに詳しくないのですが、このキノコはとても個性的で、周りの普通のキノコとは全く違っていました。 そのキノコを見ていると、なぜこのキノコがこんなに特別なのか、どんな生態を持つのか、と興味がわいてきました。私はすぐに携帯電話で検索し、ℼベロウドスモーキーキノコについて調べてみました。 すると、ℼベロウドスモーキーキノコはとても珍しい種類のキノコで、日本国内では限られた地域にしか生息していないそうです。また、このキノコは、普通のキノコとは違い、菌類と植物が複合したもので、栄養を取り入れるのに特殊な方法を使っているとのこと。さらに、ℼベロウドスモーキーキノコは、見た目からは分からないが、毒キノコに分類され、食べると命に関わるほど危険なものだそうです。 このように、私たちの周りには、見た目や常識から外れた個性的なものがあふれていることに気づかされました。ℼベロウドスモーキーキノコのように、珍しい生き物や現象に出合うと、自分の知らないことを知ることができ、好奇心や世界観が広がると思います。そんな発見と驚きがあふれる世界を、もっと積極的に探求してみたいと思います。(この例文はAIにより作成されています。特定の文字を含む文章を出力していますが内容が正確でない場合があります。)