Originally Posted by

**vinson24** Not sure if how i got to the answer is right

the question is... is this sequence strictly increasing or strictly decreasing

$\displaystyle \frac{5^{n}}{2^{n^2}}$sequence with n=1 to infinity

used $\displaystyle A_{n+1}-A_{n}$

which gave me $\displaystyle \frac{5^{n+1}}{2^{(n+1)^{2}}}*\frac{2^{n^2}}{5^n}$

You must have meant that you put $\displaystyle A_n:=\frac{5^n}{2^{n^2}}$ , and then you did $\displaystyle \frac{A_{n+1}}{A_n}$ , not $\displaystyle A_{n+1}-A_n$ ...

Does simplifying that give me

$\displaystyle \frac{5}{2^{2n+1}}$which is<1; for n is greater than or equal to 1

so the sequence is decreasing