Geometric Series Test Rather Than Integral Test

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Bashyboy
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Homework Statement


[itex]\sum_{n=1}^{\infty} \frac{1}{2^n}[/itex]


Homework Equations





The Attempt at a Solution


Could I some how manipulate this to fit a geometric series, so that I may instead use the geometric series test?
 
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[tex]\frac{1}{2^n}= \left(\frac{1}{2}\right)^n[/tex]
 
Bashyboy said:

Homework Statement


[itex]\sum_{n=1}^{\infty} \frac{1}{2^n}[/itex]

Homework Equations



The Attempt at a Solution


Could I some how manipulate this to fit a geometric series, so that I may instead use the geometric series test?

Hint:

No manipulation is required.
 
Well, I was told by my teacher that n couldn't equal one for the geometric series to be implemented, was he, perhaps, wrong?
 
Bashyboy said:
Well, I was told by my teacher that n couldn't equal one for the geometric series to be implemented, was he, perhaps, wrong?
Do you mean, n can't start at 1, it must start at zero?

If so factor 1/2 out of your series & change the index accordingly,

else,

Add 1 to your series so that it starts at n=0, and subtract 1 from your result.