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Write the sum of the series 1^2-2^2+3^2-...

Write the sum of the series `1^2-2^2+3^2-4^2+5^2-6^2...........+(2n-1)^2-(2n)^2dot`

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We have given the series `1^2-2^2+3^2-4^2+5^2-6^2...........+(2n-1)^2-(2n)^2`
It can also be write as `=1−4+9−16+25−`.... to 2n terms
`=(1−4)+(9−16)+(25−36)+`.... to n terms. (after grouping)
`=−3+(−7)+(−11)+....n` terms As the given series is given in A.P.
hence we have formula of sum of n terms = `n/2(2a(n−1)d)`
Here, `a=-3,d=-4`
...
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RD SHARMA-SOME SPECIAL SERIES-Solved Examples And Exercises
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  2. Sum of the following series to n term: 1+3+7+13+21+ ............

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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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  9. Write the sum of the series 1^2-2^2+3^2-4^2+5^2-6^2...........+(2n-1)^...

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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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  11. If sum(r=1)^n r=55 ,find sum(r=1)^n r^3.

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  12. If the sum of first n even natural numbers is equal to k times the sum...

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  13. Write the sum of 20 terms of the series: 1+1/2(1+2)+1/3(1+2+3)+

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  15. Let Sn denote the sum of the cubes of the first n natural numbers and ...

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

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  17. If 1+(1+2)/2+(1+2+3)/3+......\ n terms is S.t Then, S is equal to a. (...

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