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Hyperbolic cosine


In mathematics, hyperbolic functions are analogs of the ordinary trigonometric, or circular functions.

The basic hyperbolic functions are the hyperbolic sine "sinh" (/ˈsɪn/ or /ˈʃn/), and the hyperbolic cosine "cosh" (/ˈkɒʃ/), from which are derived the hyperbolic tangent "tanh" (/ˈtæn/ or /ˈθæn/),hyperbolic cosecant "csch" or "cosech" (/ˈkʃɛk/ or /ˈksɛ/), hyperbolic secant "sech" (/ˈʃɛk/ or /ˈsɛ/), and hyperbolic cotangent "coth" (/ˈkθ/ or /ˈkɒθ/), corresponding to the derived trigonometric functions.


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Wikipedia

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