Question -
Answer -
It is known that (r +1)th term, (Tr+1), in the binomialexpansion of (a + b)n is givenby 
.
Assuming that am occursin the (r + 1)th term of the expansion (1 + a)m + n,we obtain
Comparing the indices of a in am andin Tr + 1, we obtain
r = m
Therefore, the coefficientof am is
Assuming that an occursin the (k + 1)th term of the expansion (1 + a)m+n,we obtain
Comparing the indices of a in an andin Tk + 1, we obtain
k = n
Therefore, the coefficientof an is
Thus, from (1) and (2), it can beobserved that the coefficients of am and an inthe expansion of (1 + a)m + n areequal.