Question

if the mth term of an A.P be 1/n and the nth term be 1/m. find the 10 mnth term.

Answer 1

a+(m-1)d = 1/n                 a+(m-1)/mn=1/n
a+(n-1)d=1/m                      a-1/mn=0
(m-n)d=1/n-1/m                    a=1/mn
(m-n)d=(m-n)/mn
d=1/mn
10mnth term
1/mn +(10mn-1)1/mn
1/mn+10-1/mn
=10