If the ratio of the sum of first of term of two AP is (7x+1)(4x+2)find the ratio of the terms
Answers
Answered by
2
Answer:
Mark my answer has brainliest
Step-by-step explanation:
Let the two series' be T nand T n′ with first terms a and a ′and common differences d and d ′
The ratio of the sums of the series' S
n
and S
n
′
is given as,
S
n
′
S
n
=
[n/2][2a
′
+[n−1]d
′
]
[n/2][2a+[n−1]d]
=
4n+27
7n+1
Or,
a
′
+[(n−1)/2]d
′
a+[(n−1)/2]d
=
4n+27
7n+1
...(1)
We have to find,
T
11
′
T
11
=
a
′
+10d
′
a+10d
Choosing (n−1)/2=10 or n=21 in (1) we get
T11=
a+10d =
4(21)+27
7(21)+1
= 111148
ratio= 4:3
Similar questions