英和和英

名詞

imaginary number (複数形 imaginary numbers)

1. (complex analysis, strict sense) A number of the form bi, where b is any real number and i denotes the imaginary unit.
   • 2008, Donald A. McQuarrie, Mathematics for Physical Chemistry: Opening Doors, University Science Books, page 54,

     If ${\displaystyle a=0}$, then ${\displaystyle x=ib}$ is called an imaginary number. The message here is that we must introduce imaginary numbers in order to be able to solve quadratic equations in general.

2. (complex analysis, broad sense) A number of the form a + bi, where a and b are real numbers and b is nonzero.

使用する際の注意点

• The term is often used without rigorous definition, and at times inconsistently.
• Zero is considered both a real number and an imaginary number.
• When the broad sense is used, the term purely imaginary number (または pure imaginary number) may be used for an imaginary number in the strict sense.

同意語

• (sensu stricto): purely imaginary number

上位語

• (both senses): complex number

下位語

• (sensu lato): purely imaginary number

参考

• complex number
• real number

参照