In a G.P., the sum of the first and last term is 66, the product of the second and the last but one is 128 and the sum of the terms is 126
If an increasing G.P. is considered, then the number of terms in G.P. is
a)
9
b)
8
c)
12
d)
6
In a G.P., the sum of the first and last term is 66, the product of the second and the last but one is 128 and the sum of the terms is 126
If an increasing G.P. is considered, then the number of terms in G.P. is
a)
9
b)
8
c)
12
d)
6
Question ID - 51125 | SaraNextGen Top Answer
In a G.P., the sum of the first and last term is 66, the product of the second and the last but one is 128 and the sum of the terms is 126
If an increasing G.P. is considered, then the number of terms in G.P. is
a)
9
b)
8
c)
12
d)
6
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In a G.P., the sum of the first and last term is 66, the product of the second and the last but one is 128 and the sum of the terms is 126 |
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If an increasing G.P. is considered, then the number of terms in G.P. is |
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a) |
9 |
b) |
8 |
c) |
12 |
d) |
6 |
(d)
Let 
be the first term and 
the common ratio of the given G.P.
Further, let there be 
terms in the given G.P. Then,
(i)
Putting this value of 
in (i), we get
Putting 
in (1), we get
Putting 
in (1), we get
for an increasing G.P., 
. Now,
For decreasing G.P., 
and 
. Hence, the sum of infinite terms is 
For 
terms are 2, 4, 8, 16, 32, 64. For 
terms are 64, 32, 16, 8, 4, 2. Hence difference is 62