The mth term of an AP is n and the nth term is m. Find the (m+n)th term of this AP.

Asked by Topperlearning User | 22nd Sep, 2017, 03:29: PM

Expert Answer:

Let a and d respectively be the first term and the common difference of the AP.

Then, we have:

a + (m - 1)d = n …………(i)

And,a + (n - 1)d = m ………..(ii)

On solving (i) and (ii), we get,

d = -1 ; a = m + n - 1

am+n = a + (m + n - 1)d

= m + n -1 + (m + n - 1)(-1)

= m +n - 1 - m - n + 1

= 0

Answered by  | 22nd Sep, 2017, 05:29: PM