Question 1008318
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Hello, I have a good news for you ! :)


The general problem was just solved 
in &nbsp;<A HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/Sequences-and-series.faq.question.1008316.html>http://www.algebra.com/algebra/homework/Sequences-and-series/Sequences-and-series.faq.question.1008316.html</A>.


So, &nbsp;take the general formula and substitute &nbsp;n=9 &nbsp;there.