Question 1085527
.
<pre>
1) Find the sum of the series.

9
&#931; k^2  = {{{(n*(n+1)*(2n+1))/6}}} at n = 9     =  {{{(9*(9+1)*(2*9+1))/6}}} = calculate it on your own . . . 
k=1
</pre>

Regarding the general formula, see the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/Mathematical-induction-for-sequences-other-than-arithmetic-or-geometric.lesson>Mathematical induction for sequences other than arithmetic or geometric</A>

in this site.



Also, you have this free of charge online textbook in ALGEBRA-II in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-II - YOUR ONLINE TEXTBOOK</A>.


The referred lesson is the part of this online textbook under the topic 
<U>"Method of Mathematical induction"</U>.



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