Hyperbolic "Fourier" type infinite series for $\log(\sinh x)$ and $\log(\cosh x)$

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Hyperbolic Fourier type infinite series for $\log(\sinh x)$ and $\log(\cosh x)$ analogous to Fourier $\cos$ series for $\log(\sin x)$ and $\log(\cos x)$

$$\log(\sinh(x))=-\frac{1}{2} (i \pi )-\log (2)-\sum _{k=1}^{\infty } \frac{\cosh (2 k x)}{k} \tag{1}$$

$$\log(\cosh(x))=-\log (2)-\sum _{k=1}^{\infty } \frac{(-1)^k \cosh (2 k x)}{k} \tag{2}$$

These analogous formula were found using Mathematica, but I am not sure about the proof. Do I convert $\cosh(2kx)$ into its exponential form and proceed that way?

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Hint:

$$\sin(ix)=i\sinh(x)$$ and $$\cos(ix)=\cosh(x)$$