Solution
= Solution
The defining <exponential function> formulas for the <hyperbolic functions> give
$$
\cosh^2x-\sinh^2x
=\frac{(e^x+e^{-x})^2-(e^x-e^{-x})^2}{4}
=\boxed{1}.
$$
= Solution
The defining <exponential function> formulas for the <hyperbolic functions> give
$$
\cosh^2x-\sinh^2x
=\frac{(e^x+e^{-x})^2-(e^x-e^{-x})^2}{4}
=\boxed{1}.
$$