Question

If nth term of an AP is 2n + 1 what is the sum of its first three term

Answer 1

Answer:

a1=2(1)+1

=3

a3+2(3)+1

+7

a2=2(2)+1

=5

s3=3/2(3+7)

=15

Step-by-step explanation:

Answer 2

let first term be

2*1+1=3

second term be

2*2+1=5

third term be

2*3+1=7

sum of first three terms = 3+5+7

=15