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Integral of 1/(3*x^2-x+1) dx

Limits of integration:

from to
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The graph:

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Piecewise:

The solution

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  2                
  /                
 |                 
 |       1         
 |  ------------ dx
 |     2           
 |  3*x  - x + 1   
 |                 
/                  
0                  
$$\int\limits_{0}^{2} \frac{1}{\left(3 x^{2} - x\right) + 1}\, dx$$
Integral(1/(3*x^2 - x + 1), (x, 0, 2))
Detail solution
We have the integral:
  /               
 |                
 |      1         
 | ------------ dx
 |    2           
 | 3*x  - x + 1   
 |                
/                 
Rewrite the integrand
     1                        1                
------------ = --------------------------------
   2              /                      2    \
3*x  - x + 1      |/     ____       ____\     |
               11 ||-6*\/ 11      \/ 11 |     |
               --*||---------*x + ------|  + 1|
               12 \\    11          11  /     /
or
  /                 
 |                  
 |      1           
 | ------------ dx  
 |    2            =
 | 3*x  - x + 1     
 |                  
/                   
  
     /                              
    |                               
    |              1                
12* | --------------------------- dx
    |                       2       
    | /     ____       ____\        
    | |-6*\/ 11      \/ 11 |        
    | |---------*x + ------|  + 1   
    | \    11          11  /        
    |                               
   /                                
------------------------------------
                 11                 
In the integral
     /                              
    |                               
    |              1                
12* | --------------------------- dx
    |                       2       
    | /     ____       ____\        
    | |-6*\/ 11      \/ 11 |        
    | |---------*x + ------|  + 1   
    | \    11          11  /        
    |                               
   /                                
------------------------------------
                 11                 
do replacement
      ____         ____
    \/ 11    6*x*\/ 11 
v = ------ - ----------
      11         11    
then
the integral =
     /                      
    |                       
    |   1                   
12* | ------ dv             
    |      2                
    | 1 + v                 
    |                       
   /              12*atan(v)
--------------- = ----------
       11             11    
do backward replacement
     /                                                                     
    |                                                                      
    |              1                                                       
12* | --------------------------- dx                                       
    |                       2                                              
    | /     ____       ____\                                               
    | |-6*\/ 11      \/ 11 |                                               
    | |---------*x + ------|  + 1                   /    ____         ____\
    | \    11          11  /               ____     |  \/ 11    6*x*\/ 11 |
    |                                  2*\/ 11 *atan|- ------ + ----------|
   /                                                \    11         11    /
------------------------------------ = ------------------------------------
                 11                                     11                 
Solution is:
                 /    ____         ____\
        ____     |  \/ 11    6*x*\/ 11 |
    2*\/ 11 *atan|- ------ + ----------|
                 \    11         11    /
C + ------------------------------------
                     11                 
The answer (Indefinite) [src]
                                      /    ____           \
  /                          ____     |6*\/ 11 *(-1/6 + x)|
 |                       2*\/ 11 *atan|-------------------|
 |      1                             \         11        /
 | ------------ dx = C + ----------------------------------
 |    2                                  11                
 | 3*x  - x + 1                                            
 |                                                         
/                                                          
$$\int \frac{1}{\left(3 x^{2} - x\right) + 1}\, dx = C + \frac{2 \sqrt{11} \operatorname{atan}{\left(\frac{6 \sqrt{11} \left(x - \frac{1}{6}\right)}{11} \right)}}{11}$$
The graph
The answer [src]
                                     /  ____\
                            ____     |\/ 11 |
    ____     /  ____\   2*\/ 11 *atan|------|
2*\/ 11 *atan\\/ 11 /                \  11  /
--------------------- + ---------------------
          11                      11         
$$\frac{2 \sqrt{11} \operatorname{atan}{\left(\frac{\sqrt{11}}{11} \right)}}{11} + \frac{2 \sqrt{11} \operatorname{atan}{\left(\sqrt{11} \right)}}{11}$$
=
=
                                     /  ____\
                            ____     |\/ 11 |
    ____     /  ____\   2*\/ 11 *atan|------|
2*\/ 11 *atan\\/ 11 /                \  11  /
--------------------- + ---------------------
          11                      11         
$$\frac{2 \sqrt{11} \operatorname{atan}{\left(\frac{\sqrt{11}}{11} \right)}}{11} + \frac{2 \sqrt{11} \operatorname{atan}{\left(\sqrt{11} \right)}}{11}$$
2*sqrt(11)*atan(sqrt(11))/11 + 2*sqrt(11)*atan(sqrt(11)/11)/11
Numerical answer [src]
0.947225825099483
0.947225825099483

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