Trying to review for the exam. Can someone please help me with this series questions. Thank you

Question

Use geometric series test to determine whether converges or diverges if it converges find the sum
∞
∑. (π/2)^n
n=1

∞
∑. 3^n/(-2)^n
n=2

Answer 1

π/2 > 1 so it diverges
3^n/(-2)^n = (-1)^n * (3/2)^n and 3/2 > 1 so it diverges.
Recall the error bound on alternating series.

Answer 2

So if it's greater than one it diverges and if its less than one it converges.