Mister Exam

How do you exp(-x)/(1+exp(x))^2 in partial fractions?

An expression to simplify:

The solution

You have entered [src]
    -x   
   e     
---------
        2
/     x\ 
\1 + e / 
$$\frac{e^{- x}}{\left(e^{x} + 1\right)^{2}}$$
exp(-x)/(1 + exp(x))^2
Fraction decomposition [src]
-1/(1 + exp(x)) - 1/(1 + exp(x))^2 + exp(-x)
$$e^{- x} - \frac{1}{e^{x} + 1} - \frac{1}{\left(e^{x} + 1\right)^{2}}$$
    1          1        -x
- ------ - --------- + e  
       x           2      
  1 + e    /     x\       
           \1 + e /       
Numerical answer [src]
exp(-x)/(1.0 + exp(x))^2
exp(-x)/(1.0 + exp(x))^2
Common denominator [src]
        1         
------------------
   2*x    x    3*x
2*e    + e  + e   
$$\frac{1}{e^{3 x} + 2 e^{2 x} + e^{x}}$$
1/(2*exp(2*x) + exp(x) + exp(3*x))
Trigonometric part [src]
 -(-cosh(x) + sinh(x))  
------------------------
                       2
(1 + cosh(x) + sinh(x)) 
$$- \frac{\sinh{\left(x \right)} - \cosh{\left(x \right)}}{\left(\sinh{\left(x \right)} + \cosh{\left(x \right)} + 1\right)^{2}}$$
   -sinh(x) + cosh(x)   
------------------------
                       2
(1 + cosh(x) + sinh(x)) 
$$\frac{- \sinh{\left(x \right)} + \cosh{\left(x \right)}}{\left(\sinh{\left(x \right)} + \cosh{\left(x \right)} + 1\right)^{2}}$$
(-sinh(x) + cosh(x))/(1 + cosh(x) + sinh(x))^2