Question

The sum of the third and the 17 terms of an ap is 6 and their product is 8 find the sum of the first 16 terms of the ap

Answer 1

Answer:

Step-by-step explanation:

T3+T17=6

a+2d+a+16d=6

2a+18d=6

a+9d=3

a=3-9d

T3*T17=8

(a+2d)(a+16d)=8

Substituting value of a:

(3-9d+2d)(2-9d+16d)=8

(3-7d)(3+7d)=8

9-49d² =8

1=49d²

1=7d

d=1/7

a=12/7

S16=8(24/7+17/7)

=8(41/7)

=328/7