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real number
actual number (as opposed to a speculative number); true number
実数と整数は異なる概念だ。
Real numbers and integers are different concepts.
実数の範囲では負の平方根は求められない。
A negative square root cannot be found within the range of real numbers.
有理数も無理数もすべて実数に含まれる。
Both rational and irrational numbers are all included in the real numbers.