$$\int \frac{dx}{\sinh x}$$
Options are:
a)cosh x +c
b)log$\frac{e^x-1}{e^x+1}$
c)$\frac{\log e^{2x}}{1+e^x}+c$
d)-cosh x +c

Question

$$\int \frac{dx}{\sinh x}$$
Options are:
a)cosh x +c
b)log$\frac{e^x-1}{e^x+1}$
c)$\frac{\log e^{2x}}{1+e^x}+c$
d)-cosh x +c

ujjwal · Answer

I missed +c in option b

anonymous · Answer

Clearly, options (a) and (d) are out. 
Integrating csch(x) gives ln(tanh(x/2)). Does that help?

foolaroundmath · Answer

$$\sinh x = \frac{e^{x}-e^{-x}}{2}$$Take e^x = t
e^x dx = dt, integral now converts to
$$\int\limits \frac{2}{t^{2}-1}dt$$

Can you take it off from here ? Its just simple partial fractions

ujjwal · Answer

so, its option b.
Thanks @FoolAroundMath

ujjwal · Answer

And thanks @QuantumModulus