MUST SHOW YOUR WORK!!! Solution Apply D\'almbert ratio test.... lim n->8 |a(n+1) / a(n) | < 1 where a(n) denotes the nth term.... lim n->8 | (x/5) * (n / n+1) | = | x/ 5| < 1 therefore |x| < 5 Therefore interval of convergence is (-5 , + 5)....Read less