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Integral of (4x-1)/(x^2-4x+8) dx

Limits of integration:

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Piecewise:

The solution

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  1                
  /                
 |                 
 |    4*x - 1      
 |  ------------ dx
 |   2             
 |  x  - 4*x + 8   
 |                 
/                  
0                  
$$\int\limits_{0}^{1} \frac{4 x - 1}{\left(x^{2} - 4 x\right) + 8}\, dx$$
Integral((4*x - 1)/(x^2 - 4*x + 8), (x, 0, 1))
Detail solution
We have the integral:
  /               
 |                
 |   4*x - 1      
 | ------------ dx
 |  2             
 | x  - 4*x + 8   
 |                
/                 
Rewrite the integrand
                                     /7\      
                                     |-|      
  4*x - 1          2*x - 4           \4/      
------------ = 2*------------ + --------------
 2                2                      2    
x  - 4*x + 8     x  - 4*x + 8   /  x    \     
                                |- - + 1|  + 1
                                \  2    /     
or
  /                 
 |                  
 |   4*x - 1        
 | ------------ dx  
 |  2              =
 | x  - 4*x + 8     
 |                  
/                   
  
                           /                 
                          |                  
                          |       1          
                       7* | -------------- dx
                          |          2       
                          | /  x    \        
                          | |- - + 1|  + 1   
    /                     | \  2    /        
   |                      |                  
   |   2*x - 4           /                   
2* | ------------ dx + ----------------------
   |  2                          4           
   | x  - 4*x + 8                            
   |                                         
  /                                          
In the integral
    /               
   |                
   |   2*x - 4      
2* | ------------ dx
   |  2             
   | x  - 4*x + 8   
   |                
  /                 
do replacement
     2      
u = x  - 4*x
then
the integral =
    /                       
   |                        
   |   1                    
2* | ----- du = 2*log(8 + u)
   | 8 + u                  
   |                        
  /                         
do backward replacement
    /                                     
   |                                      
   |   2*x - 4              /     2      \
2* | ------------ dx = 2*log\8 + x  - 4*x/
   |  2                                   
   | x  - 4*x + 8                         
   |                                      
  /                                       
In the integral
    /                 
   |                  
   |       1          
7* | -------------- dx
   |          2       
   | /  x    \        
   | |- - + 1|  + 1   
   | \  2    /        
   |                  
  /                   
----------------------
          4           
do replacement
        x
v = 1 - -
        2
then
the integral =
    /                     
   |                      
   |   1                  
7* | ------ dv            
   |      2               
   | 1 + v                
   |                      
  /              7*atan(v)
-------------- = ---------
      4              4    
do backward replacement
    /                                  
   |                                   
   |       1                           
7* | -------------- dx                 
   |          2                        
   | /  x    \                         
   | |- - + 1|  + 1                    
   | \  2    /                 /     x\
   |                     7*atan|-1 + -|
  /                            \     2/
---------------------- = --------------
          4                    2       
Solution is:
                                /     x\
                          7*atan|-1 + -|
         /     2      \         \     2/
C + 2*log\8 + x  - 4*x/ + --------------
                                2       
The answer (Indefinite) [src]
  /                                                  /     x\
 |                                             7*atan|-1 + -|
 |   4*x - 1                  /     2      \         \     2/
 | ------------ dx = C + 2*log\8 + x  - 4*x/ + --------------
 |  2                                                2       
 | x  - 4*x + 8                                              
 |                                                           
/                                                            
$$\int \frac{4 x - 1}{\left(x^{2} - 4 x\right) + 8}\, dx = C + 2 \log{\left(x^{2} - 4 x + 8 \right)} + \frac{7 \operatorname{atan}{\left(\frac{x}{2} - 1 \right)}}{2}$$
The graph
The answer [src]
                       7*atan(1/2)   7*pi
-2*log(8) + 2*log(5) - ----------- + ----
                            2         8  
$$- 2 \log{\left(8 \right)} - \frac{7 \operatorname{atan}{\left(\frac{1}{2} \right)}}{2} + \frac{7 \pi}{8} + 2 \log{\left(5 \right)}$$
=
=
                       7*atan(1/2)   7*pi
-2*log(8) + 2*log(5) - ----------- + ----
                            2         8  
$$- 2 \log{\left(8 \right)} - \frac{7 \operatorname{atan}{\left(\frac{1}{2} \right)}}{2} + \frac{7 \pi}{8} + 2 \log{\left(5 \right)}$$
-2*log(8) + 2*log(5) - 7*atan(1/2)/2 + 7*pi/8
Numerical answer [src]
0.186119681896777
0.186119681896777

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