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Byju's Answer
Standard XII
Mathematics
nth Term of A.P
Find the sum ...
Question
Find the sum of first three terms of the following
sequence whose
n
t
h
term is
8
−
5
n
.
A
−
9
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B
−
6
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C
6
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D
12
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Solution
The correct option is
C
−
6
Given,
T
n
=
8
−
5
n
So,
T
1
=
8
−
5
=
3
T
2
=
8
−
5
(
2
)
=
−
2
T
3
=
8
−
5
(
3
)
=
−
7
So, Sum of first three terms
=
3
−
2
−
7
=
−
6
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0
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