Calculus Help!

So, I did this power series problem and found my summation notation, but when I found my limit it was [tex]\frac{n}{n+1}[/tex] after doing the Ratio Test and this would give ∞/∞. So with that in mind...

If the limit you got from your power series when doing a Ratio test was ∞/∞, would I have to do L'Hopital's Rule to get a number in order to define the interval of convergence? Or would that ∞/∞ tell you that it is divergent?

Respuesta :

Thdev

Answer:

Yes.

Step-by-step explanation:

You would have to use L'Hopital's Rule. Infinity/Infinity is undefined, just like 0/0 is undefined.

I just googled this.

Before trying other techniques, plug in the arrow number. If the result is:

   A number, you’re done.

    A number over zero or infinity over zero, the answer is infinity.

    A number over infinity, the answer is zero.

    0/0 or ∞/∞, use L’Hôpital’s Rule.

The thing is, when you say you got your limit, do you mean[tex]\lim_{n \to \infty} (n+1)/n[/tex] ?

This can just be found out by dividing by highest denominator power on numerator and denominator..

[tex]\lim_{n \to \infty} 1 + 1/n[/tex]

the limit of 1 is 1.

the limit of 1/x is 0.

because its equal to one it diverges.