作者llccyy (狗狗)
看板trans_math
标题[积分]
时间Fri Apr 7 00:21:13 2006
Let s(x) and c(x) be two functions satisfying s'(x)=c(x) and c'(x)=-s(x)
for all x.If s(0)=0 and c(0)=1 ,prove that [s(x)]^2+[c(x)]^2=1
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1F：→ GBRS:这个我门高微课本有ㄟ...虽然观察法可以得知是cosx与sinx 04/07 22:13
2F：→ GBRS:两种函数...但题目始终没降说...只能从定义来下手... 04/07 22:15
3F：→ GBRS:详情请看Rudin高微Special Functions那章... 04/07 22:15
4F：→ llccyy:sinx? cosx? 04/08 10:29
5F：推 GBRS:虽然是高微的东西...但其实Secial Functions那章几乎都比较偏 04/08 18:42
6F：→ GBRS:重微积分的计算...所以考出这种题目其实也不意外... 04/08 18:43