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Integral of 2/(x²+4x+8) dx

Limits of integration:

from to
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
 oo                
  /                
 |                 
 |       2         
 |  ------------ dx
 |   2             
 |  x  + 4*x + 8   
 |                 
/                  
0                  
$$\int\limits_{0}^{\infty} \frac{2}{\left(x^{2} + 4 x\right) + 8}\, dx$$
Integral(2/(x^2 + 4*x + 8), (x, 0, oo))
Detail solution
We have the integral:
  /               
 |                
 |      2         
 | ------------ dx
 |  2             
 | x  + 4*x + 8   
 |                
/                 
Rewrite the integrand
                    /2\      
                    |-|      
     2              \4/      
------------ = --------------
 2                      2    
x  + 4*x + 8   /  x    \     
               |- - - 1|  + 1
               \  2    /     
or
  /                 
 |                  
 |      2           
 | ------------ dx  
 |  2              =
 | x  + 4*x + 8     
 |                  
/                   
  
  /                 
 |                  
 |       1          
 | -------------- dx
 |          2       
 | /  x    \        
 | |- - - 1|  + 1   
 | \  2    /        
 |                  
/                   
--------------------
         2          
In the integral
  /                 
 |                  
 |       1          
 | -------------- dx
 |          2       
 | /  x    \        
 | |- - - 1|  + 1   
 | \  2    /        
 |                  
/                   
--------------------
         2          
do replacement
         x
v = -1 - -
         2
then
the integral =
  /                   
 |                    
 |   1                
 | ------ dv          
 |      2             
 | 1 + v              
 |                    
/              atan(v)
------------ = -------
     2            2   
do backward replacement
  /                               
 |                                
 |       1                        
 | -------------- dx              
 |          2                     
 | /  x    \                      
 | |- - - 1|  + 1                 
 | \  2    /                      
 |                                
/                          /    x\
-------------------- = atan|1 + -|
         2                 \    2/
Solution is:
        /    x\
C + atan|1 + -|
        \    2/
The answer (Indefinite) [src]
  /                                 
 |                                  
 |      2                    /    x\
 | ------------ dx = C + atan|1 + -|
 |  2                        \    2/
 | x  + 4*x + 8                     
 |                                  
/                                   
$$\int \frac{2}{\left(x^{2} + 4 x\right) + 8}\, dx = C + \operatorname{atan}{\left(\frac{x}{2} + 1 \right)}$$
The graph
The answer [src]
pi
--
4 
$$\frac{\pi}{4}$$
=
=
pi
--
4 
$$\frac{\pi}{4}$$
pi/4

    Use the examples entering the upper and lower limits of integration.