हिंदी

The 12th Term of the G.P. 1 a 3 X 3 , a X , a 5 X 5 , . . . - Mathematics

Advertisements
Advertisements

प्रश्न

Find :

the 12th term of the G.P.

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

उत्तर

Here,

\[\text { First term, } a = \frac{1}{a^3 x^3}\]

\[\text { Common ratio }, r = \frac{a_2}{a_1} = \frac{ax}{\frac{1}{a^3 x^3}} = a^4 x^4 \]

\[ \therefore 12th \text { term } = a_{12} = a r^{(12 - 1)} = \frac{1}{a^3 x^3}( a^4 x^4 )^{11} = a^{41} x^{41} \]

\[\text { Thus, the 12th term of the given GP is } a^{41} x^{41} .\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 20: Geometric Progression - Exercise 20.1 [पृष्ठ १०]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 11
अध्याय 20 Geometric Progression
Exercise 20.1 | Q 3.4 | पृष्ठ १०

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Find the sum to indicated number of terms in the geometric progressions 1, – a, a2, – a3, ... n terms (if a ≠ – 1).


Find the sum to indicated number of terms in the geometric progressions x3, x5, x7, ... n terms (if x ≠ ± 1).


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


Find the sum to n terms of the sequence, 8, 88, 888, 8888… .


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`


If the first and the nth term of a G.P. are a ad b, respectively, and if P is the product of n terms, prove that P2 = (ab)n.


If a, b, c and d are in G.P. show that (a2 + b2 + c2) (b2 + c2 + d2) = (ab + bc + cd)2 .


The sum of two numbers is 6 times their geometric mean, show that numbers are in the ratio `(3 + 2sqrt2) ":" (3 - 2sqrt2)`.


If a, b, c, d and p are different real numbers such that:
(a2 + b2 + c2) p2 − 2 (ab + bc + cd) p + (b2 + c2 + d2) ≤ 0, then show that a, b, c and d are in G.P.


The product of three numbers in G.P. is 216. If 2, 8, 6 be added to them, the results are in A.P. Find the numbers.


Find the sum of the following geometric series:

\[\frac{2}{9} - \frac{1}{3} + \frac{1}{2} - \frac{3}{4} + . . . \text { to 5 terms };\]


Find the sum of the following series:

7 + 77 + 777 + ... to n terms;


Find the sum of the following series:

0.5 + 0.55 + 0.555 + ... to n terms.


Find the sum of the following series:

0.6 + 0.66 + 0.666 + .... to n terms


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 the following serie to infinity:

\[1 - \frac{1}{3} + \frac{1}{3^2} - \frac{1}{3^3} + \frac{1}{3^4} + . . . \infty\]


If a, b, c are in G.P., prove that:

(a + 2b + 2c) (a − 2b + 2c) = a2 + 4c2.


If a, b, c, d are in G.P., prove that:

 (a + b + c + d)2 = (a + b)2 + 2 (b + c)2 + (c + d)2


If a, b, c, d are in G.P., prove that:

(a2 − b2), (b2 − c2), (c2 − d2) are in G.P.


If a, b, c are in G.P., then prove that:

\[\frac{a^2 + ab + b^2}{bc + ca + ab} = \frac{b + a}{c + b}\]

If pth, qth and rth terms of an A.P. and G.P. are both a, b and c respectively, show that \[a^{b - c} b^{c - a} c^{a - b} = 1\]


If A be one A.M. and pq be two G.M.'s between two numbers, then 2 A is equal to 


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

1, –5, 25, –125 …


For the G.P. if r = `1/3`, a = 9 find t7


For a G.P. a = 2, r = `-2/3`, find S6


For a G.P. if S5 = 1023 , r = 4, Find a


For a G.P. If t3 = 20 , t6 = 160 , find S7


Find the sum to n terms of the sequence.

0.5, 0.05, 0.005, ...


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,...`


Express the following recurring decimal as a rational number:

`51.0bar(2)`


A ball is dropped from a height of 10m. It bounces to a height of 6m, then 3.6m and so on. Find the total distance travelled by the ball


Select the correct answer from the given alternative.

The common ratio for the G.P. 0.12, 0.24, 0.48, is –


Select the correct answer from the given alternative.

The tenth term of the geometric sequence `1/4, (-1)/2, 1, -2,` ... is –


Answer the following:

Find the sum of the first 5 terms of the G.P. whose first term is 1 and common ratio is `2/3`


Answer the following:

Find `sum_("r" = 1)^"n" (2/3)^"r"`


The sum or difference of two G.P.s, is again a G.P.


If the sum of an infinite GP a, ar, ar2, ar3, ...... . is 15 and the sum of the squares of its each term is 150, then the sum of ar2, ar4, ar6, .... is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×