Thursday, 7 June 2018

sequences and series - Prove that limlimitsntoinfty(1frac12n+1)3n=frac1esqrte



I have this problem that I cannot seem to solve. I tried splitting it into two factors lim but that did not help because of the +1 in the denominator. So I tried multiplying both powers by \frac{2n+1}{2n+1} but that did not help either. So now I'm stuck,and don't know what to do
can someone please help? Thanks


Answer



Hint: write 3n = \dfrac{3}{2}(2n+1) - \dfrac{3}{2}, and use the fact that \displaystyle \lim_{n\to \infty} \left(1-\dfrac{1}{2n+1}\right)^{2n+1} = \dfrac{1}{e}. Can you take it from here?



No comments:

Post a Comment

real analysis - How to find lim_{hrightarrow 0}frac{sin(ha)}{h}

How to find \lim_{h\rightarrow 0}\frac{\sin(ha)}{h} without lhopital rule? I know when I use lhopital I easy get $$ \lim_{h\rightarrow 0}...