Question

Help!!!! Determine whether the following integrals converge, and if they do, to what. Integral from 4 to infinity (1/x^3) dx

Answer 1

\[\lim_{n \rightarrow \infty} \int\limits_{4}^{n} \frac{ 1 }{ x ^{3} }\]

Answer 2

does that help or do you need more...?

Answer 3

i don't know how to do it

Answer 4

evaluate the integral
=-1/(2x^2)

plug in n and 4
-1/(2n^2) - -1/(2(4)^2)

find the limit as n-> infinity
(hint: this one is super easy)

Answer 5

clear on that?

Answer 6

questions? comments? concerns?

Answer 7

I need to see you do it out please?

Answer 8

i got -1/32 ...but i think its suppose to be positive?

Answer 9

- - 1/(2(4)^2)

Answer 10

why is there 2 minuses?

Answer 11

n
-1/(2x^2) | = -1/(2n^2) - -1/(2*4^2)
4

Answer 12

4 is the lower limit of integration, n is the upper limit of integration