English

Determine whether the sum to infinity of the following G.P.s exist, if exists find them: 12,14,18,116,... - Mathematics and Statistics

Advertisements
Advertisements

Question

Determine whether the sum to infinity of the following G.P.s exist, if exists find them:

`1/2, 1/4, 1/8, 1/16,...`

Sum

Solution

Here, a = `1/2`, r = `1/2`

Since | r | = `|1/2| = 1/2 < 1`, the sum to infinity of this G.P. exist and 

S = `"a"/(1 - "r")`

= `((1/2))/(1 - 1/2)`

= `((1/2))/((1/2))`

= 1

shaalaa.com
  Is there an error in this question or solution?
Chapter 2: Sequences and Series - Exercise 2.3 [Page 33]

APPEARS IN

RELATED QUESTIONS

The 4th term of a G.P. is square of its second term, and the first term is –3. Determine its 7thterm.


The sum of first three terms of a G.P. is 16 and the sum of the next three terms is 128. Determine the first term, the common ratio and the sum to n terms of the G.P.


Find a G.P. for which sum of the first two terms is –4 and the fifth term is 4 times the third term.


If the 4th, 10th and 16th terms of a G.P. are x, y and z, respectively. Prove that x, y, z are in G.P.


Find the sum of the products of the corresponding terms of the sequences `2, 4, 8, 16, 32 and 128, 32, 8, 2, 1/2`


Find four numbers forming a geometric progression in which third term is greater than the first term by 9, and the second term is greater than the 4th by 18.


if `(a+ bx)/(a - bx) = (b +cx)/(b - cx) = (c + dx)/(c- dx) (x != 0)` then show that a, b, c and d are in G.P.


If a, b, c, d are in G.P, prove that (an + bn), (bn + cn), (cn + dn) are in G.P.


Find :

the 12th term of the G.P.

\[\frac{1}{a^3 x^3}, ax, a^5 x^5 , . . .\]


Which term of the progression 0.004, 0.02, 0.1, ... is 12.5?


The sum of three numbers in G.P. is 21 and the sum of their squares is 189. Find the numbers.


Find the sum of the following geometric progression:

2, 6, 18, ... to 7 terms;


Find the sum of the following geometric progression:

(a2 − b2), (a − b), \[\left( \frac{a - b}{a + b} \right)\] to n terms;


Find the sum of the following geometric series:

 0.15 + 0.015 + 0.0015 + ... to 8 terms;


The common ratio of a G.P. is 3 and the last term is 486. If the sum of these terms be 728, find the first term.


How many terms of the G.P. 3, \[\frac{3}{2}, \frac{3}{4}\] ..... are needed to give the sum \[\frac{3069}{512}\] ?


Find the sum of 2n terms of the series whose every even term is 'a' times the term before it and every odd term is 'c' times the term before it, the first term being unity.


Express the recurring decimal 0.125125125 ... as a rational number.


Find the rational numbers having the following decimal expansion: 

\[0 .\overline {231 }\]


If a, b, c are in G.P., prove that:

a (b2 + c2) = c (a2 + b2)


If a, b, c are in G.P., prove that the following is also in G.P.:

a3, b3, c3


If (a − b), (b − c), (c − a) are in G.P., then prove that (a + b + c)2 = 3 (ab + bc + ca)


If a, b, c are in A.P. and a, b, d are in G.P., then prove that a, a − b, d − c are in G.P.


If a, b, c are in A.P., b,c,d are in G.P. and \[\frac{1}{c}, \frac{1}{d}, \frac{1}{e}\] are in A.P., prove that a, c,e are in G.P.


If a, b, c are in A.P. and a, x, b and b, y, c are in G.P., show that x2, b2, y2 are in A.P.


Insert 5 geometric means between 16 and \[\frac{1}{4}\] .


Find the geometric means of the following pairs of number:

a3b and ab3


If S be the sum, P the product and R be the sum of the reciprocals of n terms of a GP, then P2 is equal to


The sum of an infinite G.P. is 4 and the sum of the cubes of its terms is 92. The common ratio of the original G.P. is 


Let x be the A.M. and yz be two G.M.s between two positive numbers. Then, \[\frac{y^3 + z^3}{xyz}\]  is equal to 


In a G.P. if the (m + n)th term is p and (m − n)th term is q, then its mth term is 


Check whether the following sequence is G.P. If so, write tn.

2, 6, 18, 54, …


For the following G.P.s, find Sn.

`sqrt(5)`, −5, `5sqrt(5)`, −25, ...


Express the following recurring decimal as a rational number:

`2.3bar(5)`


Find : `sum_("n" = 1)^oo 0.4^"n"`


Answer the following:

Find k so that k – 1, k, k + 2 are consecutive terms of a G.P.


Let `{a_n}_(n = 0)^∞` be a sequence such that a0 = a1 = 0 and an+2 = 2an+1 – an + 1 for all n ≥ 0. Then, `sum_(n = 2)^∞ a^n/7^n` is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×