Question

Find the sum of the first 14 terms for a sequence starting with 2, ending with 120 and common difference 2.

Answer 1

Find the sum of the first 14 terms for a sequence starting with 2, ending with 120 and common difference 2

The above asked question is that from the chapter of A.P and G.P.

This refers to arithmetic progression and geometric progression.

d is common difference, a= starting number of sequence, l= ending number of sequence.

step 1 : find  

a= 2

d=2

formula

Tn = a+(n-1)d

Sn= n/2 (a+l)

Sn= 14/2 (2+120)

=854