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Let `a_1 , a_2 , a_3,....` be terms of an A.P. if `(a_1 + a_2 +....+ a_p)/(a_1 + a_2 +...+ a_q) = p^2/q^2. p ne q ` then `a_6/a_21` equals

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CENGAGE PUBLICATION-SEQUENCES AND SERIES-All Questions
  1. Find the nth term of the AP 8, 3, -2, -7, -12,....

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  2. The sum of three consecutiveterms of an AP is 21, and the sum of the s...

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  3. Let a1 , a2 , a3,.... be terms of an A.P. if (a1 + a2 +....+ ap)/(a1 +...

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  4. Consider an A.P. a1, a2, a3,......... such that a3+a5+a8=11 and a4+a2...

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  5. If the sum of n terms of an A.P is cn (n-1) where c ne 0 then find the...

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  6. If |a|<1a n d|b|<1, then the sum of the series 1+(1+a)b+(1+a+a^2)b^2+(...

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  7. Find the sum of odd intergers from 1 to 201.

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  8. If a1, a2, a3(a1>0) are three successive terms of a G.P. with common r...

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  9. Three numbers form an increasing G.P. If the middle number is doubled,...

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  10. If S1,S2, S3, Sm are the sums of n terms of m A.P. ' s whose first ter...

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  11. If S1,S2 and S3 be respectively the sum of n, 2n and 3n terms of a G.P...

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  12. There are 4n + 1 terms in a sequence of which first 2n + 1 are in Arit...

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  13. If (p+q)t h term of a G.P. is a and its (p-q)t h term is b where a ,b ...

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  14. Find the sum of n terms of the series whose nth term is T(n)=tanx/(2^n...

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  15. Evaluate, sum(i = 0)^iinfty sum(j = 0)^infty sum(k = 0)^infty 1/(3^i c...

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  16. The first trem of a GP is -3 and the square of the second term is equa...

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  17. If log(2)(5.2^(x)+1),log(4)(2^(1-x)+1) and 1 are in A.P,then x equals

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  18. Find the geometric series whose 5th and 8th terms are 80 and 640 respe...

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  19. 0ltthetaltpi/2, if x=sum(n=0)^inftycos^(2n)theta,y=sum(n=0)^inftysin^(...

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  20. The real numbers x1, x2, x3 satisfying the equation x^3-x^2+b x+gamma=...

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