Let y=tanx. Prove that if (a) x is rational, then y is irrational. (b) x is irrational, then y is rational.?
回答 (2)
2015-09-21 11:55 am
✔ 最佳答案
Here is the proof:https://someclassicalmaths.wordpress.com/2009/07/17/nivens-proof-that-the-trigonometric-and-inverse-trigonometric-functions-are-irrational-for-rational-non-zero-arguments/
another proof:
https://books.google.com.hk/books?id=ov-IlIEo47cC&pg=PA15&source=gbs_toc_r&hl=zh-TW#v=onepage&q&f=false
2015-09-21 4:30 am
收錄日期: 2021-04-18 00:18:18
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20150920070955AAohiJG