Answer:
The identity is proved in the step-by-step explanation.
Step-by-step explanation:
The cosine hyperbolic function can be approximated by the following exponential equation:
[tex]cosh(x) = \frac{e^{x} + e^{-x}}{2}[/tex]
For [tex]cosh(-x)[/tex], we have that:
[tex]cosh(-x) = \frac{e^{-x} + e^{-(-x)}}{2} = \frac{e^{-x} + e^{x}}{2} = \frac{e^{x} + e^{-x}}{2} = cosh(x)[/tex]
Since [tex]cosh(x) = cosh(-x)[/tex], the hyperbolic cosine is an even function.
