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(xdx)/((x^2)+7x+13)

Integral of (xdx)/((x^2)+7x+13) dx

Limits of integration:

from to
v

The graph:

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Piecewise:

The solution

You have entered [src]
  1                     
  /                     
 |                      
 |            1         
 |  x*1*------------- dx
 |       2              
 |      x  + 7*x + 13   
 |                      
/                       
0                       
$$\int\limits_{0}^{1} x 1 \cdot \frac{1}{x^{2} + 7 x + 13}\, dx$$
Detail solution
We have the integral:
  /                      
 |                       
 |             1         
 | 1*x*1*------------- dx
 |        2              
 |       x  + 7*x + 13   
 |                       
/                        
Rewrite the integrand
                    /   1*2*x + 7   \                              
                    |---------------|             / -7  \          
                    |   2           |             |-----|          
          1         \1*x  + 7*x + 13/             \2*3/4/          
x*1*------------- = ----------------- + ---------------------------
     2                      2                                 2    
    x  + 7*x + 13                       /     ___         ___\     
                                        |-2*\/ 3      7*\/ 3 |     
                                        |--------*x - -------|  + 1
                                        \   3            3   /     
or
  /                        
 |                         
 |             1           
 | 1*x*1*------------- dx  
 |        2               =
 |       x  + 7*x + 13     
 |                         
/                          
  
                             /                              
                            |                               
                            |              1                
  /                     14* | --------------------------- dx
 |                          |                       2       
 |    1*2*x + 7             | /     ___         ___\        
 | --------------- dx       | |-2*\/ 3      7*\/ 3 |        
 |    2                     | |--------*x - -------|  + 1   
 | 1*x  + 7*x + 13          | \   3            3   /        
 |                          |                               
/                          /                                
--------------------- - ------------------------------------
          2                              3                  
In the integral
  /                  
 |                   
 |    1*2*x + 7      
 | --------------- dx
 |    2              
 | 1*x  + 7*x + 13   
 |                   
/                    
---------------------
          2          
do replacement
     2      
u = x  + 7*x
then
the integral =
  /                       
 |                        
 |   1                    
 | ------ du              
 | 13 + u                 
 |                        
/              log(13 + u)
------------ = -----------
     2              2     
do backward replacement
  /                                       
 |                                        
 |    1*2*x + 7                           
 | --------------- dx                     
 |    2                                   
 | 1*x  + 7*x + 13                        
 |                         /      2      \
/                       log\13 + x  + 7*x/
--------------------- = ------------------
          2                     2         
In the integral
      /                              
     |                               
     |              1                
-14* | --------------------------- dx
     |                       2       
     | /     ___         ___\        
     | |-2*\/ 3      7*\/ 3 |        
     | |--------*x - -------|  + 1   
     | \   3            3   /        
     |                               
    /                                
-------------------------------------
                  3                  
do replacement
          ___         ___
      7*\/ 3    2*x*\/ 3 
v = - ------- - ---------
         3          3    
then
the integral =
      /                       
     |                        
     |   1                    
-14* | ------ dv              
     |      2                 
     | 1 + v                  
     |                        
    /              -14*atan(v)
---------------- = -----------
       3                3     
do backward replacement
      /                                                                   
     |                                                                    
     |              1                                                     
-14* | --------------------------- dx                                     
     |                       2                                            
     | /     ___         ___\                                             
     | |-2*\/ 3      7*\/ 3 |                                             
     | |--------*x - -------|  + 1                   /    ___         ___\
     | \   3            3   /                ___     |7*\/ 3    2*x*\/ 3 |
     |                                  -7*\/ 3 *atan|------- + ---------|
    /                                                \   3          3    /
------------------------------------- = ----------------------------------
                  3                                     3                 
Solution is:
                                     /    ___         ___\
                             ___     |7*\/ 3    2*x*\/ 3 |
       /      2      \   7*\/ 3 *atan|------- + ---------|
    log\13 + x  + 7*x/               \   3          3    /
C + ------------------ - ---------------------------------
            2                            3                
The answer (Indefinite) [src]
                                                               /    ___          \
  /                                                    ___     |2*\/ 3 *(7/2 + x)|
 |                               /      2      \   7*\/ 3 *atan|-----------------|
 |           1                log\13 + x  + 7*x/               \        3        /
 | x*1*------------- dx = C + ------------------ - -------------------------------
 |      2                             2                           3               
 |     x  + 7*x + 13                                                              
 |                                                                                
/                                                                                 
$${{\log \left(x^2+7\,x+13\right)}\over{2}}-{{7\,\arctan \left({{2\,x +7}\over{\sqrt{3}}}\right)}\over{\sqrt{3}}}$$
The graph
The answer [src]
                                                        /    ___\
                                                ___     |7*\/ 3 |
                        ___     /    ___\   7*\/ 3 *atan|-------|
log(21)   log(13)   7*\/ 3 *atan\3*\/ 3 /               \   3   /
------- - ------- - --------------------- + ---------------------
   2         2                3                       3          
$$-{{7\,\arctan 3^{{{3}\over{2}}}}\over{\sqrt{3}}}+{{7\,\arctan \left({{7}\over{\sqrt{3}}}\right)}\over{\sqrt{3}}}+{{\log 21}\over{2 }}-{{\log 13}\over{2}}$$
=
=
                                                        /    ___\
                                                ___     |7*\/ 3 |
                        ___     /    ___\   7*\/ 3 *atan|-------|
log(21)   log(13)   7*\/ 3 *atan\3*\/ 3 /               \   3   /
------- - ------- - --------------------- + ---------------------
   2         2                3                       3          
$$- \frac{7 \sqrt{3} \operatorname{atan}{\left(3 \sqrt{3} \right)}}{3} - \frac{\log{\left(13 \right)}}{2} + \frac{\log{\left(21 \right)}}{2} + \frac{7 \sqrt{3} \operatorname{atan}{\left(\frac{7 \sqrt{3}}{3} \right)}}{3}$$
Numerical answer [src]
0.0278597920014529
0.0278597920014529
The graph
Integral of (xdx)/((x^2)+7x+13) dx

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