and I don't know how to do this one either:
1/4,____,4
Or this one:
_____,_______,_______,2.5 r=2
My textbook doesn't go over this either....
Thanks
recall that the terms of a geometric series are given by:
$\displaystyle a_n = ar^{n - 1}$ for $\displaystyle n = 1,2,3,4...$
where $\displaystyle a_n$ is the nth term, $\displaystyle a$ is the first term, $\displaystyle r$ is the common ratio, and $\displaystyle n$ is the current number of the term.
here we see that $\displaystyle a = \frac 14$ and $\displaystyle a_3 = ar^2 = \frac 14r^2 = 4$
solve for $\displaystyle r$ and you can find the middle term.
here you have $\displaystyle a_4 = 2.5 = ar^3 = 8a$Or this one:
_____,_______,_______,2.5 r=2
My textbook doesn't go over this either....
Thanks
solve for $\displaystyle a$ and you can find the other terms