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If a1,a2,a3,...,an be in AP whose common...

If `a_1,a_2,a_3,...,a_n` be in AP whose common difference is `d` then prove that `sum_(i=1)^n a_ia_(i+1)=n{a_1^2+na_1d+(n^2-1)/3 d^2}`.

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A DAS GUPTA-Progression, Related Inequalities and Series-Exercise
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  2. Sum the series : (1*2)+(1*2+2*3)+(1*2+2*3+3*4)+... to 12 brackets.

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  3. If a1,a2,a3,...,an be in AP whose common difference is d then prove th...

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  4. Find the sum of n terms of the series 1 *2 *3 + 2*4*6 + 3*6*9+...

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  5. Find the sum of n terms of the series 1 + 9 +24 + 46 + 75................

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  6. Find the nth term and sum to n tems of the following series: 3+6+11+18...

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  7. If tn=sum1^n n, find Sn=sum1^n tn.

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  8. Find the sum of n terms of the series 1^2 + 4^2+ 7^2 + .........

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  9. Find the sum of the series 2 + 5 + 14 +41 + 122 +.... up to n terms an...

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  10. The sum to n terms of series 1+(1/2+1/(2^2))+1+(1/2+1/(2^2)+1/(2^3)+1/...

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  11. Find the sum to n terms of the series 5+ 11 + 19 + 29+ 41+ ……

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  12. The sum of first 9 terms of the series (1^(3))/(1)+(1^(3)+2^(3))/(1+3)...

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  13. Find the sum to n terms of the series 1^(2)/(1)+(1^(2)+2^(2))/(1+2)...

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  14. Find sum n^3 from n=1 to n=100.

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  15. Evaluate sum(n=1)^n {sum(n=1)^n (2^n+3n)}.

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  17. AAn in N ,1+2x+3x^2++ndotx^(n-1)=(x in R , x!=1)

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  18. 1-4/2+7/(2^2)-10/(2^3)+

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  19. Sum to infinite terms : 1*2+2*3x+3*4*x^2+...,(|x|<1).

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  20. Evaluate : sum(r=1)^oo r^2x^(r-1),(|x|<1).

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