Question

Find the sum of the first 50 terms In An = 3n + 2

Answer 1

hello :
this arithmetic sequence the first term is : A1 = 3(1)+2=5
and common difference is r = 3
the sum of the first 50 terms is : S50 = 50/2(A1 + A50)
A50 = 3(50)+2 = 152
S50 = 50/2(5 + 152)= 3925

Answer 2

Answer with Step-by-step explanation:

The sum of first n terms of an arithmetic progression is given by:

`S(n)=(n)/(2)* (A1+An)`

We are given n=50 and we have to find S(50)

`S(50)=(50)/(2)* (A1+A50)`

A1=3×1+2=5

A50=3×50+2=152

`S(50)=(50)/(2)* (5+152)`

S(50)=25×157

=3,925

Hence, sum of the first 50 terms in An = 3n + 2 is:

3,925