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1/(x²+9)

Integral of 1/(x²+9) dx

Limits of integration:

from to
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
  1          
  /          
 |           
 |    1      
 |  ------ dx
 |   2       
 |  x  + 9   
 |           
/            
0            
$$\int\limits_{0}^{1} \frac{1}{x^{2} + 9}\, dx$$
Integral(1/(x^2 + 9), (x, 0, 1))
Detail solution
We have the integral:
  /         
 |          
 |   1      
 | ------ dx
 |  2       
 | x  + 9   
 |          
/           
Rewrite the integrand
  1            1       
------ = --------------
 2         /     2    \
x  + 9     |/-x \     |
         9*||---|  + 1|
           \\ 3 /     /
or
  /           
 |            
 |   1        
 | ------ dx  
 |  2        =
 | x  + 9     
 |            
/             
  
  /             
 |              
 |     1        
 | ---------- dx
 |      2       
 | /-x \        
 | |---|  + 1   
 | \ 3 /        
 |              
/               
----------------
       9        
In the integral
  /             
 |              
 |     1        
 | ---------- dx
 |      2       
 | /-x \        
 | |---|  + 1   
 | \ 3 /        
 |              
/               
----------------
       9        
do replacement
    -x 
v = ---
     3 
then
the integral =
  /                   
 |                    
 |   1                
 | ------ dv          
 |      2             
 | 1 + v              
 |                    
/              atan(v)
------------ = -------
     9            9   
do backward replacement
  /                       
 |                        
 |     1                  
 | ---------- dx          
 |      2                 
 | /-x \                  
 | |---|  + 1             
 | \ 3 /               /x\
 |                 atan|-|
/                      \3/
---------------- = -------
       9              3   
Solution is:
        /x\
    atan|-|
        \3/
C + -------
       3   
The answer (Indefinite) [src]
  /                    /x\
 |                 atan|-|
 |   1                 \3/
 | ------ dx = C + -------
 |  2                 3   
 | x  + 9                 
 |                        
/                         
$$\int \frac{1}{x^{2} + 9}\, dx = C + \frac{\operatorname{atan}{\left(\frac{x}{3} \right)}}{3}$$
The graph
The answer [src]
atan(1/3)
---------
    3    
$$\frac{\operatorname{atan}{\left(\frac{1}{3} \right)}}{3}$$
=
=
atan(1/3)
---------
    3    
$$\frac{\operatorname{atan}{\left(\frac{1}{3} \right)}}{3}$$
atan(1/3)/3
Numerical answer [src]
0.107250184798881
0.107250184798881
The graph
Integral of 1/(x²+9) dx

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