Integral of (2*x+1)/(x+2) dx
The solution
Detail solution
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There are multiple ways to do this integral.
Method #1
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Let u=2x.
Then let du=2dx and substitute du:
∫u+4u+1du
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Let u=u+4.
Then let du=du and substitute du:
∫uu−3du
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Rewrite the integrand:
uu−3=1−u3
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Integrate term-by-term:
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The integral of a constant is the constant times the variable of integration:
∫1du=u
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The integral of a constant times a function is the constant times the integral of the function:
∫(−u3)du=−3∫u1du
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The integral of u1 is log(u).
So, the result is: −3log(u)
The result is: u−3log(u)
Now substitute u back in:
u−3log(u+4)+4
Now substitute u back in:
2x−3log(2x+4)+4
Method #2
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Rewrite the integrand:
x+22x+1=2−x+23
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Integrate term-by-term:
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The integral of a constant is the constant times the variable of integration:
∫2dx=2x
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The integral of a constant times a function is the constant times the integral of the function:
∫(−x+23)dx=−3∫x+21dx
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Let u=x+2.
Then let du=dx and substitute du:
∫u1du
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The integral of u1 is log(u).
Now substitute u back in:
log(x+2)
So, the result is: −3log(x+2)
The result is: 2x−3log(x+2)
Method #3
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Rewrite the integrand:
x+22x+1=x+22x+x+21
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Integrate term-by-term:
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The integral of a constant times a function is the constant times the integral of the function:
∫x+22xdx=2∫x+2xdx
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Rewrite the integrand:
x+2x=1−x+22
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Integrate term-by-term:
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The integral of a constant is the constant times the variable of integration:
∫1dx=x
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The integral of a constant times a function is the constant times the integral of the function:
∫(−x+22)dx=−2∫x+21dx
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Let u=x+2.
Then let du=dx and substitute du:
∫u1du
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The integral of u1 is log(u).
Now substitute u back in:
log(x+2)
So, the result is: −2log(x+2)
The result is: x−2log(x+2)
So, the result is: 2x−4log(x+2)
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Let u=x+2.
Then let du=dx and substitute du:
∫u1du
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The integral of u1 is log(u).
Now substitute u back in:
log(x+2)
The result is: 2x+log(x+2)−4log(x+2)
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Add the constant of integration:
2x−3log(2x+4)+4+constant
The answer is:
2x−3log(2x+4)+4+constant
The answer (Indefinite)
[src]
/
|
| 2*x + 1
| ------- dx = 4 + C - 3*log(4 + 2*x) + 2*x
| x + 2
|
/
∫x+22x+1dx=C+2x−3log(2x+4)+4
The graph
−3log(3)+2+3log(2)
=
−3log(3)+2+3log(2)
Use the examples entering the upper and lower limits of integration.