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9/(x^2+9)

Integral of 9/(x^2+9) dx

Limits of integration:

from to
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
  1          
  /          
 |           
 |    9      
 |  ------ dx
 |   2       
 |  x  + 9   
 |           
/            
0            
$$\int\limits_{0}^{1} \frac{9}{x^{2} + 9}\, dx$$
Integral(9/(x^2 + 9), (x, 0, 1))
Detail solution
We have the integral:
  /         
 |          
 |   9      
 | ------ dx
 |  2       
 | x  + 9   
 |          
/           
Rewrite the integrand
            /9\    
            |-|    
  9         \9/    
------ = ----------
 2            2    
x  + 9   /-x \     
         |---|  + 1
         \ 3 /     
or
  /           
 |            
 |   9        
 | ------ dx  
 |  2        =
 | x  + 9     
 |            
/             
  
  /             
 |              
 |     1        
 | ---------- dx
 |      2       
 | /-x \        
 | |---|  + 1   
 | \ 3 /        
 |              
/               
In the integral
  /             
 |              
 |     1        
 | ---------- dx
 |      2       
 | /-x \        
 | |---|  + 1   
 | \ 3 /        
 |              
/               
do replacement
    -x 
v = ---
     3 
then
the integral =
  /                   
 |                    
 |   1                
 | ------ dv = atan(v)
 |      2             
 | 1 + v              
 |                    
/                     
do backward replacement
  /                         
 |                          
 |     1                 /x\
 | ---------- dx = 3*atan|-|
 |      2                \3/
 | /-x \                    
 | |---|  + 1               
 | \ 3 /                    
 |                          
/                           
Solution is:
          /x\
C + 3*atan|-|
          \3/
The answer (Indefinite) [src]
  /                         
 |                          
 |   9                   /x\
 | ------ dx = C + 3*atan|-|
 |  2                    \3/
 | x  + 9                   
 |                          
/                           
$$\int \frac{9}{x^{2} + 9}\, dx = C + 3 \operatorname{atan}{\left(\frac{x}{3} \right)}$$
The graph
The answer [src]
3*atan(1/3)
$$3 \operatorname{atan}{\left(\frac{1}{3} \right)}$$
=
=
3*atan(1/3)
$$3 \operatorname{atan}{\left(\frac{1}{3} \right)}$$
3*atan(1/3)
Numerical answer [src]
0.965251663189927
0.965251663189927
The graph
Integral of 9/(x^2+9) dx

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