# calculus - interval of convergence

posted by
**COFFEE** on
.

infinity of the summation n=0: ((n+2)/(10^n))*((x-5)^n)

.. my work so far. i used the ratio test

= lim (n-->infinity) | [((n+3)/(10^(n+1)))*((x-5)^(n+1))] / [((n+2)/(10^n))*((x-5)^n)] |

.. now my question is: was it ok for me to add "+1" to "n+2" to become "n+3"?

= lim (n-->infinity) | [((n+3)/(10^(n+1)))*(((x-5)^(n+1))/1)] * [((10^n)/(n+2))*(1/((x-5)^n))] |

= lim (n-->infinity) | [(((n+3)(x-5))/10)*(1/(n+2))] |

how do i finish this so that i could find the endpoints? please help. thank you.

nvmd. i think i got it.