Question

if (m+1)th term of an ap is twice the(n+1)th term, prove that(3m+1)th term is twice the(m+n+1)th term

Answer 1

solve first given part to get -> a=d(n-m)
substitute the values in the next part and prove it is wrong .

Answer 2

it is not correct relation ....that (3m+1)th term is not twice the (m+n+1)th term