Co-efficient of t in the expansion of, ( + p)m - 1 + ( + p)m - 2 ( + q) + ( + p)m - 3 ( + q)2 + ...... ( + q)m - 1 where- q and pq is :1.2.3.4.

Dear VISHWESH

given series is geometric progression

find the sum of the series which is equal to

    =(α +p)^m-1 [{(α +q)/(α+p)}^m  -1 ] /[{(α +q)/(α+p)}  -1]

simplyfy it

=[(α +q)^m -(α+p)^m]/(q-p)

now find the coeffiecient of α^t in this expression

 =[^mC_t q^m-t  - ^mC_t p^m-t]/(q-p)

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