Question

a1+a2+a3…+an is an arithmetic series, what is the sum?

Answer 1

The sum is just what you wrote! ^_^

Answer 2

all we have to do find the sum of first n of AP series with first term as a1 and common difference d ( which u can calculate by subtracting next term with its previous term
ex: d = a2 - a1 )
now sum is
\[\sum = \frac{ n }{ 2 }(2a+(n-1)d)\]

Answer 3

thank you

Answer 4

Its oKay