Is the Integral of 1/(x^2*lnx) Solvable Using Elementary Functions?

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  • #1
JustaNickname
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∫dx/(x^2*lnx)

What I`ve seen on the web but I don`t think is right:
u= lnx *** what we have here isn't lnx but (lnx)^-1... This is why I doubt that's the right solution
du = dx/x
dv = dx/x^2
v = -1/x

=-lnx/x + ∫dx/x^2
=-lnx/x - 1/x + C

Let me know if it is correct, thanks!
 
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  • #2
I didn't check if it is correct myself, but you never really need someone to check if an integral (like this) is correct. Just differentiate it.
 
  • #3
JustaNickname said:
∫dx/(x^2*lnx)

What I`ve seen on the web but I don`t think is right:
u= lnx *** what we have here isn't lnx but (lnx)^-1... This is why I doubt that's the right solution
du = dx/x
dv = dx/x^2
v = -1/x

=-lnx/x + ∫dx/x^2
=-lnx/x - 1/x + C

Let me know if it is correct, thanks!

Maple 14 gets a non-elementary function for this integral; that is, it cannot be done in terms of elementary functions of the type you have used.

RGV
 

FAQ: Is the Integral of 1/(x^2*lnx) Solvable Using Elementary Functions?

1. What is the integral of 1/(x^2*lnx)?

The integral of 1/(x^2*lnx) is equal to -1/lnx + C, where C is the constant of integration.

2. Is the integral of 1/(x^2*lnx) a definite or indefinite integral?

The integral of 1/(x^2*lnx) is an indefinite integral, as it does not have specific limits of integration.

3. Can the integral of 1/(x^2*lnx) be evaluated using any integration techniques?

Yes, the integral of 1/(x^2*lnx) can be evaluated using the substitution method or integration by parts.

4. Are there any restrictions on the value of x in the integral of 1/(x^2*lnx)?

Yes, the integral of 1/(x^2*lnx) is only defined for positive values of x, as the natural logarithm function is only defined for positive numbers.

5. Can the integral of 1/(x^2*lnx) be simplified further?

No, the integral of 1/(x^2*lnx) cannot be simplified any further as it is already in its most simplified form.

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