What does it mean, that cosine, sine, tangens etc, is hyperbolic?:)
Definitions:
hyperbolic sine: sinh(x) = (ex - e-x)/2 (pronounced shine!)
hyperbolic cosine: cosh(x) = (ex + e-x)/2
hyperbolic tangent: tanh(x) = (ex - e-x)/(ex + e-x) (pronounced tansh!)
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