有人可以给我解释一下RATIONAL 和IRRATIONAL NUMBER的区别吗rational number and irrational number

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有人可以给我解释一下RATIONAL 和IRRATIONAL NUMBER的区别吗rational number and irrational number

有人可以给我解释一下RATIONAL 和IRRATIONAL NUMBER的区别吗rational number and irrational number
有人可以给我解释一下RATIONAL 和IRRATIONAL NUMBER的区别吗
rational number and irrational number

有人可以给我解释一下RATIONAL 和IRRATIONAL NUMBER的区别吗rational number and irrational number
有理数和无理数
有理数(rational number):能精确地表示为两个整数之比的数.
如3,-98.11,5.72727272……,7/22都是有理数.
整数和通常所说的分数都是有理数.有理数还可以划分为正有理数,0和负有理数.
无理数指无限不循环小数 如:π
有理数和无理数的区别
只要有循环节便都可化为分数,自然便是有理数.
我曾经推理过把推理过把循环小数化为分数的方法,且看这个规律:
0.1111...=1/9
0.121212...=12/99=4/33
0.123123123...=123/999=41/333
0.142857142857142857...=142857/999999=1/7
所以如果循环节是从第一位小数开始的,如循环节x有n位,则此数=x/(10^n-1)
如果不是,也可以化为分数:
1.05555...=1+5/90=19/18
0.32010101...=32/100+1/9900=3169/9900
0.999...=9/9=1
所以即使循环节有百亿兆位也是可以化为分数的,也是有理数;而无理数不论顺到多少位也找不出循环节来.

Rational numbers are those can be expressed as a/b, where a and b are integers. Examples are: all integers, fractions, terminating decimals, or repeating non-terminating decimals (eg. 0.333333...= 1/3...

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Rational numbers are those can be expressed as a/b, where a and b are integers. Examples are: all integers, fractions, terminating decimals, or repeating non-terminating decimals (eg. 0.333333...= 1/3) But irrational numbers are those cannot be expressed as a/b, such as square root 2, which are non-terminating and non-repeating decimals.

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有理数、无理数