# algebra

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

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2. 👎
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1. ∑ (-2)^n-1
n=2
= -2 + 4 - 8 + 16 - ...

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

so what do you think ?

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Reiny

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