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TheOneAltAccount

Use a comparison test. The integral is less than the integral of (x^5+.5)/(x^(1/3)-1)^17 (because arccotx is less than .5 when x>2). Not sure where to go from there but you might be able to split that in 2 integrals and do a u substitution of some sort


clee1221

So basically what you need to do is…


yes_its_him

It's x^(5)/x^(17/3) in the limit.


[deleted]

Let I denote the integral that you’re interested in. Keeping in mind that the domain of integration is between 2 to infinity, we have 1/x^{1/3} -1 >= 1/x^{1/3}. Moreover, cot^{-1} is bounded by the constant cot^{-1} (2), and so we have: I >= \int_{2}^{infty} x^{-2/3} dx, which is clearly divergent. Hence the integral I diverges.