2016年4月15日 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …

2015年4月20日 · Using this formula to decompose $\cos z = i$ into real and imaginary parts gives the (equivalent) ...

2017年8月2日 · $\begingroup$ $\cos z=2$ iff $\cosh iz=2$. $\endgroup$ – Angina Seng. Commented Aug 2, 2017 at 11:46

2017年9月15日 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …

2016年12月3日 · I am trying to prove that $ \overline {\cos(z)} = \cos(\bar z)$ I have tried this myself but I can't see where I have gone wrong. I'd like to continue to try to prove it using the …

2015年5月5日 · The idea is to apply the same technique used in one of the answers of this problem Maximum of $|\sin(z)|$ as $\{z: |z| \leq 1 \} $ Use the identity: $$\vert\cos …

Solving $\cos A + \cos B + \cos C = 0$ and $\sin A + \sin B + \sin C = 0$ using complex numbers Hot Network Questions Building an 8080 based computer

2019年5月12日 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …

This also proves that $\cos z + i \sin z = (\cos x + i\sin x)(\cos y + i\sin y)^i$. Share. Cite. Follow ...

2014年5月13日 · If it didn't, then $\cos(z):\hat{\mathbb{C}}\to\hat{\mathbb{C}}$ would be a holomorphic function between compact Riemann surfaces (since $\infty$ would either be a …