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Integral of (x*dx)/(2+x+x^2) dx

Limits of integration:

from to
v

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The solution

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  1              
  /              
 |               
 |      x        
 |  ---------- dx
 |           2   
 |  2 + x + x    
 |               
/                
0                
$$\int\limits_{0}^{1} \frac{x}{x^{2} + \left(x + 2\right)}\, dx$$
Integral(x/(2 + x + x^2), (x, 0, 1))
Detail solution
We have the integral:
  /             
 |              
 |     x        
 | ---------- dx
 |          2   
 | 2 + x + x    
 |              
/               
Rewrite the integrand
             / 2*x + 1  \                            
             |----------|            / -1  \         
             | 2        |            |-----|         
    x        \x  + x + 2/            \2*7/4/         
---------- = ------------ + -------------------------
         2        2                             2    
2 + x + x                   /     ___       ___\     
                            |-2*\/ 7      \/ 7 |     
                            |--------*x - -----|  + 1
                            \   7           7  /     
or
  /               
 |                
 |     x          
 | ---------- dx  
 |          2    =
 | 2 + x + x      
 |                
/                 
  
                       /                            
                      |                             
                      |             1               
  /                2* | ------------------------- dx
 |                    |                     2       
 |  2*x + 1           | /     ___       ___\        
 | ---------- dx      | |-2*\/ 7      \/ 7 |        
 |  2                 | |--------*x - -----|  + 1   
 | x  + x + 2         | \   7           7  /        
 |                    |                             
/                    /                              
---------------- - ---------------------------------
       2                           7                
In the integral
  /             
 |              
 |  2*x + 1     
 | ---------- dx
 |  2           
 | x  + x + 2   
 |              
/               
----------------
       2        
do replacement
         2
u = x + x 
then
the integral =
  /                     
 |                      
 |   1                  
 | ----- du             
 | 2 + u                
 |                      
/             log(2 + u)
----------- = ----------
     2            2     
do backward replacement
  /                               
 |                                
 |  2*x + 1                       
 | ---------- dx                  
 |  2                             
 | x  + x + 2                     
 |                    /         2\
/                  log\2 + x + x /
---------------- = ---------------
       2                  2       
In the integral
     /                            
    |                             
    |             1               
-2* | ------------------------- dx
    |                     2       
    | /     ___       ___\        
    | |-2*\/ 7      \/ 7 |        
    | |--------*x - -----|  + 1   
    | \   7           7  /        
    |                             
   /                              
----------------------------------
                7                 
do replacement
        ___         ___
      \/ 7    2*x*\/ 7 
v = - ----- - ---------
        7         7    
then
the integral =
     /                      
    |                       
    |   1                   
-2* | ------ dv             
    |      2                
    | 1 + v                 
    |                       
   /              -2*atan(v)
--------------- = ----------
       7              7     
do backward replacement
     /                                                              
    |                                                               
    |             1                                                 
-2* | ------------------------- dx                                  
    |                     2                                         
    | /     ___       ___\                                          
    | |-2*\/ 7      \/ 7 |                                          
    | |--------*x - -----|  + 1                 /  ___         ___\ 
    | \   7           7  /              ___     |\/ 7    2*x*\/ 7 | 
    |                                -\/ 7 *atan|----- + ---------| 
   /                                            \  7         7    / 
---------------------------------- = -------------------------------
                7                                   7               
Solution is:
                                /  ___         ___\
                        ___     |\/ 7    2*x*\/ 7 |
       /         2\   \/ 7 *atan|----- + ---------|
    log\2 + x + x /             \  7         7    /
C + --------------- - -----------------------------
           2                        7              
The answer (Indefinite) [src]
                                                   /    ___          \
  /                                        ___     |2*\/ 7 *(1/2 + x)|
 |                        /         2\   \/ 7 *atan|-----------------|
 |     x               log\2 + x + x /             \        7        /
 | ---------- dx = C + --------------- - -----------------------------
 |          2                 2                        7              
 | 2 + x + x                                                          
 |                                                                    
/                                                                     
$$\int \frac{x}{x^{2} + \left(x + 2\right)}\, dx = C + \frac{\log{\left(x^{2} + x + 2 \right)}}{2} - \frac{\sqrt{7} \operatorname{atan}{\left(\frac{2 \sqrt{7} \left(x + \frac{1}{2}\right)}{7} \right)}}{7}$$
The graph
The answer [src]
                            /    ___\             /  ___\
                    ___     |3*\/ 7 |     ___     |\/ 7 |
                  \/ 7 *atan|-------|   \/ 7 *atan|-----|
log(4)   log(2)             \   7   /             \  7  /
------ - ------ - ------------------- + -----------------
  2        2               7                    7        
$$- \frac{\log{\left(2 \right)}}{2} - \frac{\sqrt{7} \operatorname{atan}{\left(\frac{3 \sqrt{7}}{7} \right)}}{7} + \frac{\sqrt{7} \operatorname{atan}{\left(\frac{\sqrt{7}}{7} \right)}}{7} + \frac{\log{\left(4 \right)}}{2}$$
=
=
                            /    ___\             /  ___\
                    ___     |3*\/ 7 |     ___     |\/ 7 |
                  \/ 7 *atan|-------|   \/ 7 *atan|-----|
log(4)   log(2)             \   7   /             \  7  /
------ - ------ - ------------------- + -----------------
  2        2               7                    7        
$$- \frac{\log{\left(2 \right)}}{2} - \frac{\sqrt{7} \operatorname{atan}{\left(\frac{3 \sqrt{7}}{7} \right)}}{7} + \frac{\sqrt{7} \operatorname{atan}{\left(\frac{\sqrt{7}}{7} \right)}}{7} + \frac{\log{\left(4 \right)}}{2}$$
log(4)/2 - log(2)/2 - sqrt(7)*atan(3*sqrt(7)/7)/7 + sqrt(7)*atan(sqrt(7)/7)/7
Numerical answer [src]
0.162620188068886
0.162620188068886

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