If the sum of first n terms of G.P. is S...

If the sum of first n terms of G.P. is S and the sum of its first 2n terms is 5S, then show that the sum of its first 3n terms is 21S.

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If the sum of first n terms of a G.P is p and the sum of the first 2n terms is 3p,show that the sum of first 3n terms is7p.

If the sum of the first n terms of a G.P. = p and the sum of the first 2n terms = 3p, show that the sum of first 3n terms = 7p.

If the sum of sirst n terms of a G.P is p.sum of its first 2n terms is 3p,Prove that the sum of its first 3n terms is 7p.

The sum of first P terms of an A.P. is equal to the sum of its first Q terms. Show that the sum of its first (P+Q) terms is zero.

If the sum of first p terms of an A.P. is equal to the sum of the first q terms, then find the sum of the first (p + q) terms.

The sum of the first 4 terms of a G.P. is 40 and the sum of first 8 terms is 3280. Obtain the G.P.

An A.P. consists of n terms. If the sum of its first three terms is x and the sum of the last three terms is y, then show that, the sum of all the terms of the A.P. is (n)/(6)(x+y) .

The sum of first p terms of an A.P. is (p^(2))/(n) and the sum of its first q(!= p) terms is (q^(2))/(n) . Show that the sum of its first n terms will be n.

The sum of first 6 terms of a G.P. is 9 times the sum of its first 3 terms. Find the common ratio of the G.P.

The nth term of an A.P. is p and the sum of its first n terms is q. Prove that its first term is (1)/(n)(2q-p n) .

CHHAYA PUBLICATION-SEQUENCE AND SERIES-Exercise 9 C (Long Answer Type Questions)

If S be the sum, P the product and R the sum of the reciprocal of n te...
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If S(1), S(2), S(3) be respectively the sums of n, 2n and 3n terms of ...
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If the sum of first n terms of G.P. is S and the sum of its first 2n t...
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If S(n) = 1 + (1)/(2) + (1)/(2^(2))+….+(1)/(2^(n-1)), find the least v...
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If u(1), u(2), u(3),… form a G.P. with common ratio k, find the sum of...
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Find the sum to n terms of the following series: (x+1/x)^2+(x^2+1/(x^2...
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If the first term, common ratio and the sum of first n terms of a G.P....
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When a certain golf-ball is dropped on a piece of pavement, it bounces...
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If the A.M. of two numbers be twice their G.M., prove that two numbers...
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If A and G be the A.M. and G.M. of two numbers , show that the numbers...
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If a, b, c form an A.P. and b, c, a form a G.P., show that (1)/(c ), (...
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If the arithmetic mean of y and z be x and that of (1)/(x) and (1)/(y)...
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The sum of three numbers in A.P. is 15. If 1, 4 and 19 are added to th...
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The sum of three numbers in A.P. is 18. If 2, 2, 6 are added respectiv...
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Three terms are in G.P. Their product is 216. If 4 be added to the fir...
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Find the sum to n terms of each of the following series : 1 + 11 + 1...
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Find the sum to n terms of each of the following series : 2 + 22 + ...
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0.8 + 0.88 + 0.888 + …
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Find the sum to n terms of each of the following series : 0.6 + 0.6...
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Find the sum to n terms of each of the following series : 1 + 4 + 1...
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