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avatar+7 

Ah, ok, i just really try to avoid creating new posts to avoid spam and to keep things organized, i'll know from now on.

Thank you so much for your answer it actually helped me a ton. Once you know what you're doing it becomes so easy. At least i think i've done it correctly. :p

So my original problem was: $$\displaystyle \lim_{n\rightarrow \infty}\frac{5^{n-2}-3^{n+1}}{4^{n-1}+5^n}$$

The steps that i took: (i've skipped some steps as i cba to write every single detail, it would just take too much time)$$\displaystyle\lim_{n\rightarrow \infty}\frac{\frac{5^{n-2}}{5^n}}{\frac{4^{n-1}}{5^n}+\frac{5^n}{5^n}} - \lim_{n\rightarrow \infty}\frac{\frac{3^{n+1}}{5^n}}{\frac{4^{n-1}}{5^n}+\frac{5^n}{5^n}} = \lim_{n\rightarrow \infty}\frac{5^{-2}}{\left(\frac{4^n}{5^n}\right)*4^{-1} + 1} - \lim_{n\rightarrow \infty}\frac{\left(\frac{3^n}{5^n}\right)*3}{\left(\frac{4^n}{5^n}\right)*4^{-1} + 1} = \frac{\frac{1}{25}}{0+1} - \frac{0}{0+1} = \frac{1}{25}$$

 Jan 9, 2015

Best Answer 

 #1
avatar+118608 
+5

Hi again

I'm on my phone so it is a bit hard to see properly.  Looks good though.  Do you fully understand?

I Found it easiet to use neg indices rather than do everything as fractions but it makes no difference.

 

When I said write a new post I did not mean to start a new thread.  I just meant a new post on the original thread.  LOL  :)

 Jan 9, 2015
 #1
avatar+118608 
+5
Best Answer

Hi again

I'm on my phone so it is a bit hard to see properly.  Looks good though.  Do you fully understand?

I Found it easiet to use neg indices rather than do everything as fractions but it makes no difference.

 

When I said write a new post I did not mean to start a new thread.  I just meant a new post on the original thread.  LOL  :)

Melody Jan 9, 2015
 #2
avatar+7 
0

Haha, now i get it. Thank you. ;)

 Jan 9, 2015

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