Secant of i/Proof 2

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Theorem

$\sec i = \dfrac {2 e} {e^2 + 1}$


Proof

\(\ds \sec i\) \(=\) \(\ds \sech 1\) Hyperbolic Secant in terms of Secant
\(\ds \) \(=\) \(\ds \frac 2 {e^1 + e^{-1} }\) Definition of Hyperbolic Secant
\(\ds \) \(=\) \(\ds \frac {2 e} {e^2 + 1}\) multiplying denominator and numerator by $e$

$\blacksquare$