Which of the following gives the sum of the first terms of an arithmetic progression…

MATHEMATICS · Single correct · A Level · Mathematics · Sequences and series · Sequences and series

Problem

Which of the following gives the sum of the first

n

terms of an arithmetic progression whose first term is

a

and common difference is

d

? (a)

n\,[2a+(n-1)d]

(b)

\dfrac{n}{2}\,[2a+nd]

(c)

\dfrac{n}{2}[2a+(n-1)d]

(d)

2a+(n-1)d