Question

74. If mth term of A.P. is n and nth term of A.P. is m then, the
(m+n)th
term is:
​

Answer 1

Step-by-step explanation:

ANSWER

Using the formula for mth term, we get

a

m

=a

1

+(m−1)d

Hence

a

1

+(m−1)d=n...(i)

Similarly

a

1

+(n−1)d=m ...(ii)

Subtracting (ii) from (i)

d(m−1−n+1)=n−m

d(m−n)=n−m

d=−1.

a

1

+(m−1)(−1)=n

a

1

−m+1=n

a

1

=m+n−1

Hence (m+n)

th

term is

a

m+n

=a

1

+(m+n−1)d

=(m+n−1)−(m+n−1)

=0.