Integral of 13xarctgxdx dx
The solution
Detail solution
-
The integral of a constant times a function is the constant times the integral of the function:
∫13xatan(x)1dx=13∫xatan(x)dx
-
Use integration by parts:
∫udv=uv−∫vdu
Let u(x)=atan(x) and let dv(x)=x.
Then du(x)=x2+11.
To find v(x):
-
The integral of xn is n+1xn+1 when n=−1:
∫xdx=2x2
Now evaluate the sub-integral.
-
The integral of a constant times a function is the constant times the integral of the function:
∫2(x2+1)x2dx=2∫x2+1x2dx
-
Rewrite the integrand:
x2+1x2=1−x2+11
-
Integrate term-by-term:
-
The integral of a constant is the constant times the variable of integration:
∫1dx=x
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−x2+11)dx=−∫x2+11dx
-
The integral of x2+11 is atan(x).
So, the result is: −atan(x)
The result is: x−atan(x)
So, the result is: 2x−2atan(x)
So, the result is: 213x2atan(x)−213x+213atan(x)
-
Add the constant of integration:
213x2atan(x)−213x+213atan(x)+constant
The answer is:
213x2atan(x)−213x+213atan(x)+constant
The answer (Indefinite)
[src]
/ 2
| 13*x 13*atan(x) 13*x *atan(x)
| 13*x*atan(x)*1 dx = C - ---- + ---------- + -------------
| 2 2 2
/
∫13xatan(x)1dx=C+213x2atan(x)−213x+213atan(x)
The graph
13 13*pi
- -- + -----
2 4
−213+413π
=
13 13*pi
- -- + -----
2 4
−213+413π
Use the examples entering the upper and lower limits of integration.