Question

Consider the infinite geometric series below.
a. Write the first 4 terms of the series
b. Does the series diverge or converge?
c. If the series has a sum, find the sum.
∞
∑ (-2)^n-1
n=2
not sure how to do this at all

Answer 1

∞
∑ (-2)^n-1
n=2

= -2 + 4 - 8 + 16 - 32 + 64 - ...
= (-2 + 4) + (- 8 + 16) + ( - 32 + 64) + ( - ...
= 2 + 8 + 32 + .....

So, what do you think?

Answer 2

i have no clue