Question 1124305
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \  S\ =\ \frac{n}{2}\(2a\ +\ (n\ -\ 1)d\)]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \  n\(2a\ +\ (n\ -\ 1)d\)\ =\ 2S]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \  2a\ +\ (n\ -\ 1)d\ =\ \frac{2S}{n}]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \  (n\ -\ 1)d\ =\ \frac{2S}{n}\ -\ 2a]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \  d\ =\ \frac{\frac{2S}{n}\ -\ 2a}{n\ -\ 1}]
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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