The product of three consecutive term of a g.p is _64 and the first term is four times the third. find the term.
a r^n * ar^(n+1) * a r^(n+2)
= a^3 r^(3n+3) = 64
so
a r^(n+1) = 4
a r^n = 4 a r^(n+2)
1 = 4 r^(n+2)/r^n
1/4 = r^2
r = + or - 1/2
say n = 0
r = 1/2
(a) ( a/2) (a/4) = 64
a^3 /8 = 64
a = 8
so
8 4 2 Yeah it works :)