ratio is 12^n
if first term is 6, then second is 18, third is 6+144....
the second term of a goemetric progression is 12 more than the first term.Find the third term of goemetric progression?
2 answers
ar - a = 12 , (given)
a(r-1) = 12
a = 12/(r-1)
let r be any value except r = 1
e.g. let r = 2, then a = 12, terms are 12, 24 , 48, ....
let r = 3, then a = 6, terms are 6, 18, 54, ...
let r = 7, then a = 2, terms are 2, 14, 98, ....
let r = 3.5, then a = 4.8, terms are 4.8, 16.8, 58.8, ...
notice that each is a GP and the difference between the first two terms is 12
a(r-1) = 12
a = 12/(r-1)
let r be any value except r = 1
e.g. let r = 2, then a = 12, terms are 12, 24 , 48, ....
let r = 3, then a = 6, terms are 6, 18, 54, ...
let r = 7, then a = 2, terms are 2, 14, 98, ....
let r = 3.5, then a = 4.8, terms are 4.8, 16.8, 58.8, ...
notice that each is a GP and the difference between the first two terms is 12
2 answers