I would like to fit it as :
y = a x + b tanh(c x) + d sinh(e x)
where a,b, c, d and e are the variables that I change to do the fittings.
=B$3*A11+B$4*TANH(B$5*A11)+B$6*SINH(B$7*A11)
See sample file.
Tested with LibreOffice 6.4.7.2 (x86); OS: Windows 6.1.
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