以 i 开头的数学词汇 | 玄数

2012-10-07
i   虚数单位
虚数

icosahedron   二十面体
A regular polyhedron bounded by 20 equilateral triangle faces, with 12 vertices and 30 edges.

identity   恒等式;同一性
An equation which states that two expressions are equal for all values of any variables that occur. Such as

x2 – y2 = (x + y)(x – y)

imaginary number   虚数
A number of the form a + bi, where i = √-1, a and b are real numbers and b ≠ 0.
虚数

Imperial System   英制
Conforming to standards or definitions legally established in Britain: relating to a system of measurement in which weight is measured in pounds, length is measured in feet, and volume is measured in pints.

improper fraction   假分数
An arithmetic fraction whose numerator is greater than or equal to the denominator—for example, 5/3, 4/4.

incenter   内心
The center of the circle inscribed in a triangle, that point where the bisectors of the angles of a triangle or of a regular polygon intersect.
三角形圆心 triangle angle bisector

inch   英寸
A unit of length in the US Customary and British Imperial systems, equal to 1/12 of a foot (2.54 centimeters).

incircle of triangle   三角形的内切圆
A circle inscribed within a triangle.
incircle of triangle

included angle   夹角
The angle between the free-stream vector and the longitudinal axis of a body.

increase   增多,提高
To become greater or larger in amount, number, value, etc.

independent event   独立事件
Two events are statistically independent if the probability of their occurring jointly equals the product of their respective probabilities. Also known as stochastic independence.

index   指数;索引

  • A number or symbol, often written as a subscript or superscript to a mathematical expression, that indicates an operation to be performed, an ordering relation, or a use of the associated expression. In the equation 42 = 16, the number 2 is an index.
  • Computers: a value that identifies and is used to locate a particular element within a data array or table.

inequality   不等式
A mathematical statement indicating that two quantities are not equal, represented by the symbol <, >, or ≠, meaning less than, greater than, and not equal to.