Power Reduction Formulas/Hyperbolic Cosine Squared/Proof 1

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Theorem

$\cosh^2 x = \dfrac {\cosh 2 x + 1} 2$


Proof

\(\ds 2 \cosh^2 x - 1\) \(=\) \(\ds \cosh 2 x\) Double Angle Formula for Hyperbolic Cosine: Corollary $1$
\(\ds \cosh^2 x\) \(=\) \(\ds \frac {\cosh 2 x + 1} 2\) solving for $\cosh^2 x$

$\blacksquare$