在Degree模式下隨便輸入任何數值,然後不停按cos,最後會停留的數值是什麼?
計算機cos問題
2010-02-18 2:39 am
回答 (5)
2010-02-25 11:06 pm
✔ 最佳答案
這是屬於rate of convergence的話題，需要使用http://en.wikipedia.org/wiki/Rate_of_convergence內的資料進行分析。2010-02-25 15:06:00 補充：
圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/iteration/fixpointiteration00.jpg
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參考資料：
http://hk.knowledge.yahoo.com/question/question?qid=7006072201658 + http://en.wikipedia.org/wiki/Rate_of_convergence#Convergence_speed_for_iterative_methods + my applied maths knowledge
2010-03-03 17:44:40 補充：
Yahoo!知識+的系統經常發生故障，搞到我那篇回答成日顯示唔到！
tonyleung052，其實我有答到嘢嫁，你可以選定我做最佳解答先，這樣的情況，最怕進入投票區後冇哂競爭力。
2010-02-20 9:08 am
如果用Newton's Method就要留意一D野，因為要用到cos既derivative，
但理論上計算derivative既時候係唔可以用degree去計算……
但理論上計算derivative既時候係唔可以用degree去計算……
2010-02-19 3:01 am
^^doraemonpaul發問果時可能係中五~~
2010-02-20 01:56:43 補充：
係牙...EMK...其實我都有諗過呢個問題...但點解計出黎既ans都啱既?
2010-02-20 01:56:43 補充：
係牙...EMK...其實我都有諗過呢個問題...但點解計出黎既ans都啱既?
2010-02-18 8:41 am
要搵呢個停留既值.
要理解下佢會停留既原因先.
就係呢個值cosine左之後會出番同樣既值
所以呢個值可以let做x
cos x = x
但係點樣搵我都唔知..
所以.都係用番計數機計到個值喇.
就係0.999847741喇.
2010-02-19 00:10:49 補充：
好勁呀...
Newton's formula
又上一課
讚好!
要理解下佢會停留既原因先.
就係呢個值cosine左之後會出番同樣既值
所以呢個值可以let做x
cos x = x
但係點樣搵我都唔知..
所以.都係用番計數機計到個值喇.
就係0.999847741喇.
2010-02-19 00:10:49 補充：
好勁呀...
Newton's formula
又上一課
讚好!
2010-02-18 4:29 am
xp的小算 盤
0.9998477415310881129598107686798
0.9998477415310881129598107686798
收錄日期: 2021-04-11 01:22:39
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100217000051KK01067