Differentiation

$\frac{1}{2 \sqrt{\sqrt{\cosh (3)}}}\left(1+\frac{\sinh (3)}{\sqrt{\cosh (3)}}\right)$

$\frac{1}{2 \sqrt{\sqrt{\cosh (3)}}}\left(\log 3-\frac{\sinh (3)}{\sqrt{\cosh (3)}}\right)$

$\frac{\log 3 \sqrt{\cosh (3)}-\sinh (3)}{2(\cosh (3))^{\frac{3}{4}}}$

$\frac{\sqrt{\cosh (3)}-\sinh (3)}{2(\cosh (3))^{\frac{3}{4}}}$