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Find the sum to 'n' terms of 3.1^(2)+5.2...

Find the sum to 'n' terms of `3.1^(2)+5.2^(2)+7.3^(2)+`........

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`T_(n)=` (nth term of 3,5,7….) nth term of `1^(2),2^(2),3^(2)`........)
`=[3+(n-1)(2)].n^(2)=(2n+1)n^(2)=2n^(3)+n^(2)`
`=[3+(n-1)(2)].n^(2)=(2n+1)n^(2)=2n^(3)+n^(2)`
`=2((n(n+1))/(2))^(2)+(n(n+1)(2n+1))/(6)`
`=(n^(2)(n+1)^(2))/(2)+(n(n+1)(2n+1))/(6)=(n(n+1))/(2)[n(n+1)+(2n+1)/(3)]`
`=(n(n+1))/(2)[(3n^(2)+5n+1)/(3)]=(n(n+1)(3n^(2)+5n+1))/(6)`
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