How do you find the sum of the infinite geometric series 7 + 21 + 63 + 189 + . . .?

Nov 18, 2015

Infinity (oo)

Explanation:

If the common ratio is greater than 1, than the sum will not converge.

For this problem, $r = \frac{21}{7} = 3 > 1$

Sum $= \infty$

Hope that helped