Question

If the ratio of sum of n terms of two APs is (n+1):(n-1), then the ratio of
their m th terms is:
(a) (m +1): 2m
(b) (m + 1) : (m - 1)
(c) (2m - 1): (m + 1)
(d) m: (m-1)
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Answer 1

Answer:

a and d is not an ap other questions you need difference,a and the correct formula is

Step-by-step explanation:

sn=n/2(a+(n-1)d) or sn=n/2a+l.

Answer 2

Answer:

(m+1) : (m-1)

Step-by-step explanation:

Let ,a= first term

d=common difference of A.P¹

A=first term

D=common difference of A.P²

Given: a+(n-1)d /A+(n-1)D = n+1/n-1

For m th term ,

a+(m-1)d /A+(m-1)D

Compairing this equation with above equation ,

m-1 = n-1

m = n

Substitute this value in equation a+(n-1)d /A+(n-1)D = n+1/n-1

So, ratio of m th terms = m+1 : m-1