I'm interested, why are $\cosh$ and $\cos$ related by the imaginary unit like$$\cos (x)=\cosh (ix)?$$Is there any visual proof? How can be circle related to hyperbola by complex unit?
2026-04-04 03:20:39.1775272839
Why are $\cosh$ and $\cos$ related by the imaginary unit?
162 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in TRIGONOMETRY
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