Advertisements
Advertisements
प्रश्न
The fifth term of a G.P. is 81 and its second term is 24. Find the geometric progression.
उत्तर
Let the first term of the G.P. be a and its common ratio be r.
5th term = 81 `=>` ar4 = 81
2nd term = 24 `=>` ar = 24
Now, `(ar^4)/(ar) = 81/24`
`=> r^3 = 27/8`
`=> r = 3/2`
ar = 24
`=> a xx 3/2 = 24`
`=>` a = 16
∴ G.P. = a, ar, ar2, ar3, ..............
= `16, 24, 16 xx (3/2)^2, 16 xx (3/2)^3,.........`
= 16, 24, 36, 54, ........
APPEARS IN
संबंधित प्रश्न
Which term of the G.P.:
`-10, 5/sqrt(3), -5/6,....` is `-5/72`?
Find the geometric progression with 4th term = 54 and 7th term = 1458.
If a, b and c are in G.P., prove that : log a, log b and log c are in A.P.
If a, b, c are in G.P. and a, x, b, y, c are in A.P., prove that `1/x + 1/y = 2/b`
If a, b, c are in G.P. and a, x, b, y, c are in A.P., prove that `a/x + c/y = 2`
Q 3.1
Q 3.3
The sum of three numbers in G.P. is `39/10` and their product is 1. Find the numbers.
Find the 5th term of the G.P. `5/2, 1, .........`
The first two terms of a G.P. are 125 and 25 respectively. Find the 5th and the 6th terms of the G.P.