don't understand this limit problem please help
i dont understand why she did that
divide top and bottom by \(n^2\) so you can more easily see which terms dominate
but if you do that in the bottom for example n^3/n^2 you get n not 1/n
$$\frac{3n^2+2n}{\sqrt{n^3+n^2+1}}\cdot\frac{1/n^2}{1/n^2}=\frac{3n^2+2n}{\sqrt{n^3+n^2+1}}\cdot\frac{1/n^2}{\sqrt{1/n^4}}=\frac{3+2/n}{\sqrt{1/n+1/n^2+1/n^4}}$$ so you can clearly
oh so you square it when there is a square root?
Actually he did that..
Oh sorry, that was someone else you did that..
see that in the limit as \(n\to\infty\), the square root tends to \(0\) while the top tends to \(3\); this tells us the terms 'blow up' as \(n\) grows larger and larger since the denominator gets ever smaller
\[\sqrt{\frac{1}{x^2}} = \frac{1}{x} = \sqrt{\frac{1}{x^2}}\]
*who..
When you take x inside squares, it becomes \(x^2\)..
*square root brackets..
oh okay i see
i have one more question
where did the 8 in this problem come from?
the distance between the vertex and focus (\(-4\)) is equal to the distance between the vertex and directrix
so you are add -4+-4?
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