Pre Calc
posted by MW .
Find the geometric sequence with
t(5)= 2
and
t(7)= 8
find a
How do I do this?

Well, a geometric sequence is of the form;
a, ar, a(r^2), a(r^3), ... , a(r^n)
where t(0) = a, t(1) = ar etc.
[the sequence 1, 1/2, 1/4, 1/8, 1/16,...
is geometric with a = 1 and r = 1/2]
Ok, hope that helps!