Производная tanh(x)^2

Вы ввели

    2   
tanh (x)

$$\tanh^{2}{\left (x \right )}$$

Первая производная

/          2   \        
\2 - 2*tanh (x)/*tanh(x)

$$\left(- 2 \tanh^{2}{\left (x \right )} + 2\right) \tanh{\left (x \right )}$$

Вторая производная

  /         2   \ /           2   \
2*\-1 + tanh (x)/*\-1 + 3*tanh (x)/

$$2 \left(\tanh^{2}{\left (x \right )} - 1\right) \left(3 \tanh^{2}{\left (x \right )} - 1\right)$$

Третья производная

   /         2   \ /           2   \        
-8*\-1 + tanh (x)/*\-2 + 3*tanh (x)/*tanh(x)

$$- 8 \left(\tanh^{2}{\left (x \right )} - 1\right) \left(3 \tanh^{2}{\left (x \right )} - 2\right) \tanh{\left (x \right )}$$