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AL rationality 1
2010-02-22 12:48 am
回答 (2)
2010-02-22 1:14 am
✔ 最佳答案
y = √3 - √2y + √2 = √3
y^2 + 2 + 2y√2 = 3
√2 = (1 - y^2)/2y
If y = √3 - √2 is rational , that means (1 - y^2)/2y is rational ,then √2 is
rational. But we know √2 is not rational . It is impossible.
So √3 - √2 is not rational.
2010-02-22 8:07 am
if √3-√2 is rational, then 1/(√3-√2)=√3+√2 is rational
so,[(√3+√2)-(√3-√2)]/2=√2 is rational(contradition)
so,[(√3+√2)-(√3-√2)]/2=√2 is rational(contradition)
收錄日期: 2021-04-21 22:13:27
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100221000051KK01107