Hyperbolic Cosine Function is Even/Proof 2
Jump to navigation
Jump to search
Theorem
- $\map \cosh {-x} = \cosh x$
Proof
| \(\ds \map \cosh {-x}\) | \(=\) | \(\ds \map \cos {-i x}\) | Hyperbolic Cosine in terms of Cosine | |||||||||||
| \(\ds \) | \(=\) | \(\ds \map \cos {i x}\) | Cosine Function is Even | |||||||||||
| \(\ds \) | \(=\) | \(\ds \cosh x\) | Hyperbolic Cosine in terms of Cosine |
$\blacksquare$