What is the Correct Integral Value for Divergent or Convergent?

AI Thread Summary
The integral discussed is ∫_9^{∞} (1/x^(6/5)) dx, which is evaluated to determine convergence or divergence. The initial calculation of the integral was incorrect; the correct primitive function is -5/x^(1/5). When evaluating the limits, the value at 9 should be recalculated using the correct integrand format as x^(-6/5). The limit approaches infinity, indicating that the integral diverges. Clarification on the correct setup and evaluation is essential for accurate results.
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\int_9^{inf} \frac{1}{x^{6/5}}

first thing i did was found the integral of the function

\frac{5}{x^{-1/5}}

then plug in inf(i will name it b) and 9

\frac{5}{b^{-1/5}} - \frac{5}{9^{-1/5}}
now i will find the lim -> inf

well for \frac{5}{9^{-1/5}}, it's equal to 7.759

now for \frac{5}{b^{-1/5}}, it looks like INF, but when i try to submit my answer, it tells me that I'm wrong.

anyone know what I'm doing wrong?
 
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The primitive function is wrong, it should be

-\frac{5}{x^{1/5}}.
 
Therefore,not only the limit,but also the numerical value for 9 is wrong...You should have written the integrand as x^{-\frac{6}{5}}.

Daniel.
 
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