Evaluate 1 x 2^2 + 3 x 4^2 + 5 x 6^2 +... to n terms
I have been using (2n-1)(2n^2) as my nth term. After finding my sum to n terms, i have been substituting a value in, continuously it is not coming out as intended. Possibly my nth term is incorrect. I have been using the rth term expressed as a polynomial in r method.
Thanks.
The sum of 4n^2, would be 4n(n+1)(2n+1)/6 if i am not mistaken.
However i am coming up with a sum to n terms of 2n(n+1)(3n^2+n-1)/3. When substituting values n>1. I am coming out 4 ahead of what i should be. Not sure where i am going wrong.
I had an idiotic typo , I have corrected it now
As far as answer is concerned
Sum of x terms
Put 2 , sum should come out to be = 4+48 =52
So lets put x= 2 in the answer
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Your mistake was that you considered the nth term
= (2n-1)(2n^2)
However it should be = (2n-1)(2n)^2