If the sum of the first terms of an arithmetic progression is directly proportional to
MATHEMATICS · Single correct · A Level · Mathematics · Sequences and series · Sequences and series
Problem
If the sum of the first n terms of an arithmetic progression is directly proportional to n, which of the following must be true about the progression?
(a) The common difference is one.
(b) Each term equals its position number.
(c) The common difference is zero.
(d) The first term is zero.