\[ \int \frac {1}{\sqrt {1-\tanh ^2(x)}} \, dx \]
Optimal antiderivative \[ \frac {\tanh \! \left (x \right )}{\sqrt {\mathrm {sech}\! \left (x \right )^{2}}} \]
command
integrate(1/(1-tanh(x)**2)**(1/2),x)
Sympy 1.10.1 under Python 3.10.4 output
\[ \int \frac {1}{\sqrt {1 - \tanh ^{2}{\left (x \right )}}}\, dx \]
Sympy 1.8 under Python 3.8.8 output
\[ \frac {\tanh {\left (x \right )}}{\sqrt {1 - \tanh ^{2}{\left (x \right )}}} \]