Question

The sum of third term and seventh term is 6 and there product is 8 find the 16th term

Answer 1

let the terms be a+2d and a+6d
2a+8d=6
=a+4d=3.....(1)
(a+2d)(a+6d)=8
a^2+8ad+12d^2-8=0
substitute d from (1)..solve eqn.. get a.. then d... and put in a+15d to get sixteenth term