Determine the series is conditionally or absolutely convergent.

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This is the problem:

$$\sum_{n=1}^\infty (-\frac{1}{2})^n$$

How can we decide the series is a conditionally or an absolutely convergent?

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Does $\sum_{n=1}^\infty\left|\left(-\frac{1}{2}\right)^n\right|$ converge? If yes, then the series is absolutely convergent. If not, but the series $\sum_{n=1}^\infty \left(-\frac{1}{2}\right)^n$ still converges, then it is conditionally convergent. If neither converge then the series is divergent.

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For $|x|<1$ $$\frac{1}{1+x}=\sum_{n=0}^{\infty}(-x)^n=1+\sum_{n=1}^{\infty}(-x)^n$$