2 × 2 = 4
4 × 2 = 8
8 × 2 = 16
16 × 2 = 32
6*3=18
9*5=45
18*7=126
45*9=405
The given sequence appears to be obtained by dividing the previous term by 3:
2187 ÷ 3 = 729
729 ÷ 3 = 243
243 ÷ 3 = 81
81 ÷ 3 = 27
27 ÷ 3 = 9
9 ÷ 3 = 3
10 × 4 = 40
40 × 4 = 160
160 × 4 = 640
640 × 4 = 2560
Now, let's examine the differences between consecutive terms:
17 − 6 = 11
39 − 17 = 22
72 − 39 = 33
The pattern of differences: +11, +22, +33 → increasing by 11 each time.
Next difference should be: +44
So,
72 + 44 = 116
Explanation: Differences follow a pattern: +11, +22, +33, +44.
The formula #S_oo=a_1/(1-r)#
#a_1=-10# and #r=1/2#
#S_oo=-10/(1-1/2)#
#S_oo=-20#
Sh1-9-2023
GP series = 4, 8, 16, 32, ... 512.
FORMULA USED:
Tn = ar(n-1)
SOLUTION:
⇒ 512 = 4 × 2(n - 1)
⇒ 128 = 2(n - 1)
⇒ 27 = 2(n - 1)
Now comparing powers we obtain;
⇒ n - 1 = 7
⇒ n = 8
The series obtained by adding the terms of a geometric sequence is called a geometric series
The common ratio of a geometric sequence cannot be zero because if it were, the sequence would become a series of zeros, which is not considered a geometric sequence.
Get instant updates and alerts directly from our site.
Install this app on your device for quick access right from your home screen.