+118619 wie forme ich " (e^i*pi + e^-i*pi ) / (2) um?
\(\frac{(e^{i*pi} + e^{-i*pi} ) }{ (2) }\\ =\frac{e^{pi*i} + e^{-pi*i} }{ 2 }\\ =\frac{ cos(\pi)+isin(\pi)+cos(-\pi)+isin(-\pi) }{ 2 }\\ =\frac{ cos(\pi)+isin(\pi)+cos(\pi)-isin(\pi) }{ 2 }\\ =\frac{ 2cos(\pi) }{ 2 }\\ =cos(\pi)\\ =-1\)
