Since the problem doesn't specify, I'll assume we are asked to find the derivative of the function \( f(t) = t \cosh t \).
The hyperbolic cosine function, \(\cosh t\), is defined as:
\[
\cosh t = \frac{e^t + e^{-t}}{2}
\]
To find the derivative of \( f(t) = t
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