What is the smallest integer that can possibly be the sum of an infinite geometric series whose first term is 9?
Thanks so much!
Note that we are trying to minimze this sum for some value of r
S = 9 / (1 - r)
If r = -1/2 the sum is 6
If r = -4/5 the sum is 5
If r = -5/4 the sum is 4
But l r l must be < 1 ......so r = -5/4 isn't allowed
So.....it appears that the sum is minimized to an integer whenever r = -4/5 and the minimized sum is 5