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Sum of the following series to n term: 2...

Sum of the following series to `n` term: `2+4+7+11+16+....... `

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`S_n=2+4+7+11+16+......n` terms
`S_(n-1)=2+4+7+11+16+....n-1` terms
`T_n=S_n+S_(n-1)=2+2+3+4+5+6+....n=1+(n(n+1))/2=1+1/2(n^2+n)`
`=sum T_n=sum 1+1/2(sum n^2+sum n)`
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RD SHARMA-SOME SPECIAL SERIES-Solved Examples And Exercises
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  3. Sum of the following series to n term: \ 1+3+6+10+15+.............

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  8. Write the sum of the series 2+4+6+8+...........+2n

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  10. Write the sum of n term for a series whose r^(t h) term is: r+2^r.

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  16. If sumn=210, then sumn^2=

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