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(x)/(x^2+3x+4)

Integral of (x)/(x^2+3x+4) dx

Limits of integration:

from to
v

The graph:

from to

Piecewise:

The solution

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  1                
  /                
 |                 
 |       x         
 |  ------------ dx
 |   2             
 |  x  + 3*x + 4   
 |                 
/                  
0                  
$$\int\limits_{0}^{1} \frac{x}{x^{2} + 3 x + 4}\, dx$$
Integral(x/(x^2 + 3*x + 4), (x, 0, 1))
Detail solution
We have the integral:
  /                 
 |                  
 |        x         
 | 1*------------ dx
 |    2             
 |   x  + 3*x + 4   
 |                  
/                   
Rewrite the integrand
               /  1*2*x + 3   \                              
               |--------------|             / -3  \          
               |   2          |             |-----|          
     x         \1*x  + 3*x + 4/             \2*7/4/          
------------ = ---------------- + ---------------------------
 2                    2                                 2    
x  + 3*x + 4                      /     ___         ___\     
                                  |-2*\/ 7      3*\/ 7 |     
                                  |--------*x - -------|  + 1
                                  \   7            7   /     
or
  /                   
 |                    
 |        x           
 | 1*------------ dx  
 |    2              =
 |   x  + 3*x + 4     
 |                    
/                     
  
                           /                              
                          |                               
                          |              1                
  /                    6* | --------------------------- dx
 |                        |                       2       
 |   1*2*x + 3            | /     ___         ___\        
 | -------------- dx      | |-2*\/ 7      3*\/ 7 |        
 |    2                   | |--------*x - -------|  + 1   
 | 1*x  + 3*x + 4         | \   7            7   /        
 |                        |                               
/                        /                                
-------------------- - -----------------------------------
         2                              7                 
In the integral
  /                 
 |                  
 |   1*2*x + 3      
 | -------------- dx
 |    2             
 | 1*x  + 3*x + 4   
 |                  
/                   
--------------------
         2          
do replacement
     2      
u = x  + 3*x
then
the integral =
  /                     
 |                      
 |   1                  
 | ----- du             
 | 4 + u                
 |                      
/             log(4 + u)
----------- = ----------
     2            2     
do backward replacement
  /                                     
 |                                      
 |   1*2*x + 3                          
 | -------------- dx                    
 |    2                                 
 | 1*x  + 3*x + 4                       
 |                        /     2      \
/                      log\4 + x  + 3*x/
-------------------- = -----------------
         2                     2        
In the integral
     /                              
    |                               
    |              1                
-6* | --------------------------- dx
    |                       2       
    | /     ___         ___\        
    | |-2*\/ 7      3*\/ 7 |        
    | |--------*x - -------|  + 1   
    | \   7            7   /        
    |                               
   /                                
------------------------------------
                 7                  
do replacement
          ___         ___
      3*\/ 7    2*x*\/ 7 
v = - ------- - ---------
         7          7    
then
the integral =
     /                      
    |                       
    |   1                   
-6* | ------ dv             
    |      2                
    | 1 + v                 
    |                       
   /              -6*atan(v)
--------------- = ----------
       7              7     
do backward replacement
     /                                                                   
    |                                                                    
    |              1                                                     
-6* | --------------------------- dx                                     
    |                       2                                            
    | /     ___         ___\                                             
    | |-2*\/ 7      3*\/ 7 |                                             
    | |--------*x - -------|  + 1                   /    ___         ___\
    | \   7            7   /                ___     |3*\/ 7    2*x*\/ 7 |
    |                                  -3*\/ 7 *atan|------- + ---------|
   /                                                \   7          7    /
------------------------------------ = ----------------------------------
                 7                                     7                 
Solution is:
                                    /    ___         ___\
                            ___     |3*\/ 7    2*x*\/ 7 |
       /     2      \   3*\/ 7 *atan|------- + ---------|
    log\4 + x  + 3*x/               \   7          7    /
C + ----------------- - ---------------------------------
            2                           7                
The answer (Indefinite) [src]
                                                         /    ___          \
  /                                              ___     |2*\/ 7 *(3/2 + x)|
 |                          /     2      \   3*\/ 7 *atan|-----------------|
 |      x                log\4 + x  + 3*x/               \        7        /
 | ------------ dx = C + ----------------- - -------------------------------
 |  2                            2                          7               
 | x  + 3*x + 4                                                             
 |                                                                          
/                                                                           
$${{\log \left(x^2+3\,x+4\right)}\over{2}}-{{3\,\arctan \left({{2\,x+ 3}\over{\sqrt{7}}}\right)}\over{\sqrt{7}}}$$
The graph
The answer [src]
                              /    ___\               /    ___\
                      ___     |5*\/ 7 |       ___     |3*\/ 7 |
                  3*\/ 7 *atan|-------|   3*\/ 7 *atan|-------|
log(8)   log(4)               \   7   /               \   7   /
------ - ------ - --------------------- + ---------------------
  2        2                7                       7          
$$-{{3\,\arctan \left({{5}\over{\sqrt{7}}}\right)}\over{\sqrt{7}}}+{{ 3\,\arctan \left({{3}\over{\sqrt{7}}}\right)}\over{\sqrt{7}}}+{{ \log 8}\over{2}}-{{\log 4}\over{2}}$$
=
=
                              /    ___\               /    ___\
                      ___     |5*\/ 7 |       ___     |3*\/ 7 |
                  3*\/ 7 *atan|-------|   3*\/ 7 *atan|-------|
log(8)   log(4)               \   7   /               \   7   /
------ - ------ - --------------------- + ---------------------
  2        2                7                       7          
$$- \frac{3 \sqrt{7} \operatorname{atan}{\left(\frac{5 \sqrt{7}}{7} \right)}}{7} - \frac{\log{\left(4 \right)}}{2} + \frac{3 \sqrt{7} \operatorname{atan}{\left(\frac{3 \sqrt{7}}{7} \right)}}{7} + \frac{\log{\left(8 \right)}}{2}$$
Numerical answer [src]
0.0789301896116776
0.0789301896116776
The graph
Integral of (x)/(x^2+3x+4) dx

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