Question

Plz plz someone help me out with this

Answer 1

option D

`a_(1)=6561 and a_(n)=(1)/(3)a_(n-1)`

Explanation:

`a_(3) = 729\\\\a_(4) = 243\\\\r = (a_(4))/(a_(3))\\\\r=(243)/(729)\\\\r=(1)/(3)`

Recursive rule: Next term is obtained by multiplying (1/3) wiht the previous term

`a_(n)=(1)/(3)*a_(n-1)`

`a_(3) = (1)/(3)*a_(2)\\\\\\729 = (1)/(3)*a_(2)\\\\\\729*3=a_(2)\\\\a_(2) = 2187\\\\\\`

`a_(2)=(1)/(3)*a_(1)\\\\\\2187=(1)/(3)*a_(1)\\\\\\2187*3=a_(1)\\\\a_(1)=6561`