$\large{\begin{array} {l c l }
\frac{d}{dx} \sin x &= &\cos x \\
\frac{d}{dx} \cos x &= &\sin x \\
\frac{d}{dx} \sinh x &= &\cosh x \\
\frac{d}{dx} \cosh x &= &\sinh x \end{array}}$

One of the above equations is wrong, which one?

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