Integral of (x^2-1)/(x+1) dx
The solution
Detail solution
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There are multiple ways to do this integral.
Method #1
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Rewrite the integrand:
x+1x2−1=x−1
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Integrate term-by-term:
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The integral of xn is n+1xn+1 when n=−1:
∫xdx=2x2
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The integral of a constant is the constant times the variable of integration:
∫(−1)dx=−x
The result is: 2x2−x
Method #2
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Rewrite the integrand:
x+1x2−1=x+1x2−x+11
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Integrate term-by-term:
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Rewrite the integrand:
x+1x2=x−1+x+11
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Integrate term-by-term:
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The integral of xn is n+1xn+1 when n=−1:
∫xdx=2x2
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The integral of a constant is the constant times the variable of integration:
∫(−1)dx=−x
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Let u=x+1.
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+1)
The result is: 2x2−x+log(x+1)
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The integral of a constant times a function is the constant times the integral of the function:
∫(−x+11)dx=−∫x+11dx
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Let u=x+1.
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+1)
So, the result is: −log(x+1)
The result is: 2x2−x−log(x+1)+log(x+1)
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Now simplify:
2x(x−2)
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Add the constant of integration:
2x(x−2)+constant
The answer is:
2x(x−2)+constant
The answer (Indefinite)
[src]
/
|
| 2 2
| x - 1 x
| ------ dx = C + -- - x
| x + 1 2
|
/
∫x+1x2−1dx=C+2x2−x
The graph
Use the examples entering the upper and lower limits of integration.