Find the limit of the function algebraically. limit as x approaches zero of quantity x squared plus three divided by x to the fourth power.
\[\lim_{x \rightarrow 0} \frac{ x^2+3 }{ x^4 }\]
you can take the limit of the numerator, and then limit of the denominator. (I think )
No, you can't do that because the denominator tends to 0.
I mean this, \[\lim_{x \rightarrow 0 }~\frac{x^2+3}{x^4}\] \[\Large~\frac{ \lim_{x \rightarrow 0 }~(x^2+3)}{\lim_{x \rightarrow 0 }x^4}\] \[\Large~\frac{ \lim_{x \rightarrow 0 }~(x^2+3)}{(\lim_{x \rightarrow 0 }x)^4}\]
and it would be equivalent to ∞
You can separate them, but it doesn't help solve the problem.
yes, it doesn't.
I don't find anything better though.
Well, normally what you would do is factor the top in bottom and then cancel out any repeated roots. If the number approached is still a root of the denominator, then you have an asymptote. This means the limit will be undefined, infinite, or negatively infinite.
yes, it is ∞, because it is unfactorable...
(In this case ∞)
In this case we can use: \[ \lim_{x\to 0}\frac 1{|x|} = \infty \]If we really want to use limit rules.
\[ \lim_{x\to 0}\frac{x^2+3}{x^4} = \lim_{x\to0}\frac{1}{x^2} +3 \lim_{x\to0}\frac{1}{x^4} = \left(\lim_{x\to0}\frac{1}{|x|} \right)^2+3 \left(\lim_{x\to0}\frac{1}{|x|}\right)^4 = \infty \]
Though even doing that is a bit sketchy due to the fact that the limits don't approach a finite number.
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