Answer
$0.5$
Work Step by Step
$\int1/x^{3}$ = $-x^{-2}/2$ = $-1/(2x^{2})$
$-1/(2*10^{2})$ - $-1/(2*1^{2})$ = 0.495
$-1/(2*100^{2})$ - $-1/(2*1^{2})$ = 0.49995
$-1/(2*1000^{2})$ - $-1/(2*1^{2})$ = 0.4999995
as x approaches infinity the number gets closer and closer to 0.5, meaning
$\lim\limits_{x \to \infty}$ $-1/(2*x^{2})$ - $(-1)/(2*1^{2}) = 0.5$