- #1
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I don't understand how they got rid of the negative.
l = absolute, but they aren't used anyways.
[tex]\mid \S_n - frac{a}{1 - R} \mid = \mid a( \frac{1 - r^n}{1-r} ) - \frac{a}{1-r}\mid[/tex]
[tex]= \mid \frac{a r^n}{1-r} \mid[/tex]
I'm getting...
[tex]= \mid \frac{-a r^n}{1-r} \mid[/tex]
I always miss negatives, but I don't think I did this time.
l = absolute, but they aren't used anyways.
[tex]\mid \S_n - frac{a}{1 - R} \mid = \mid a( \frac{1 - r^n}{1-r} ) - \frac{a}{1-r}\mid[/tex]
[tex]= \mid \frac{a r^n}{1-r} \mid[/tex]
I'm getting...
[tex]= \mid \frac{-a r^n}{1-r} \mid[/tex]
I always miss negatives, but I don't think I did this time.
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