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Integral of 1/(x^2+8x+25) dx

Limits of integration:

from to
v

The graph:

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Piecewise:

The solution

You have entered [src]
  2                 
  /                 
 |                  
 |        1         
 |  ------------- dx
 |   2              
 |  x  + 8*x + 25   
 |                  
/                   
0                   
$$\int\limits_{0}^{2} \frac{1}{\left(x^{2} + 8 x\right) + 25}\, dx$$
Integral(1/(x^2 + 8*x + 25), (x, 0, 2))
Detail solution
We have the integral:
  /                
 |                 
 |       1         
 | ------------- dx
 |  2              
 | x  + 8*x + 25   
 |                 
/                  
Rewrite the integrand
      1                 1         
------------- = ------------------
 2                /         2    \
x  + 8*x + 25     |/  x   4\     |
                9*||- - - -|  + 1|
                  \\  3   3/     /
or
  /                  
 |                   
 |       1           
 | ------------- dx  
 |  2               =
 | x  + 8*x + 25     
 |                   
/                    
  
  /                 
 |                  
 |       1          
 | -------------- dx
 |          2       
 | /  x   4\        
 | |- - - -|  + 1   
 | \  3   3/        
 |                  
/                   
--------------------
         9          
In the integral
  /                 
 |                  
 |       1          
 | -------------- dx
 |          2       
 | /  x   4\        
 | |- - - -|  + 1   
 | \  3   3/        
 |                  
/                   
--------------------
         9          
do replacement
      4   x
v = - - - -
      3   3
then
the integral =
  /                   
 |                    
 |   1                
 | ------ dv          
 |      2             
 | 1 + v              
 |                    
/              atan(v)
------------ = -------
     9            9   
do backward replacement
  /                               
 |                                
 |       1                        
 | -------------- dx              
 |          2                     
 | /  x   4\                      
 | |- - - -|  + 1                 
 | \  3   3/               /4   x\
 |                     atan|- + -|
/                          \3   3/
-------------------- = -----------
         9                  3     
Solution is:
        /4   x\
    atan|- + -|
        \3   3/
C + -----------
         3     
The answer (Indefinite) [src]
  /                           /4   x\
 |                        atan|- + -|
 |       1                    \3   3/
 | ------------- dx = C + -----------
 |  2                          3     
 | x  + 8*x + 25                     
 |                                   
/                                    
$$\int \frac{1}{\left(x^{2} + 8 x\right) + 25}\, dx = C + \frac{\operatorname{atan}{\left(\frac{x}{3} + \frac{4}{3} \right)}}{3}$$
The graph
The answer [src]
  atan(4/3)   atan(2)
- --------- + -------
      3          3   
$$- \frac{\operatorname{atan}{\left(\frac{4}{3} \right)}}{3} + \frac{\operatorname{atan}{\left(2 \right)}}{3}$$
=
=
  atan(4/3)   atan(2)
- --------- + -------
      3          3   
$$- \frac{\operatorname{atan}{\left(\frac{4}{3} \right)}}{3} + \frac{\operatorname{atan}{\left(2 \right)}}{3}$$
-atan(4/3)/3 + atan(2)/3
Numerical answer [src]
0.0599511665974928
0.0599511665974928

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