]]>https://www.mathisfunforum.com/profile.php?id=2060892018-10-03T13:13:18Zhttps://www.mathisfunforum.com/viewtopic.php?pid=405809#p405809Could you fix your LaTeX? The first two LaTeX codes were not rendered properly.]]>https://www.mathisfunforum.com/profile.php?id=1884562018-10-03T10:43:52Zhttps://www.mathisfunforum.com/viewtopic.php?pid=405805#p405805Let r be a real number; and J^2=-1. Then and
Thus
In my proof I didn't use any extension of the exponential function to complex numbers; but just some (very rough) estimates for