>mfw sequences and series

What's giving you trouble senpai?

Calc II?

>>8489114
Calc II or analysis

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>>8489144
Why does this work? The limit that we found is of n+1/n, NOT of the original series. We never found the limit of the original series.
>>8489155
Yes. The class wasn't too hard up until now.

>>8489182
The test for divergence. If a series converges the limit of the sequence in the series should be zero. If the limit is not zero you will be adding numbers forever which are increasing your series. I'm not very good at explaining.

>>8489199
oops nevermind I'm retarded.

That is the sequence for the original series I'm pretty sure. Looks like they try the ratio test for it then use the divergence test which they probably should've done first to conclude that the series is divergent.

>>8489222
Yup, you're right, guess I'm retarded. Maybe I should switch to a liberal arts major.

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>calc 1-3 is derivatives, integrals, and series respectively at my uni
>multivariable is its own course
>go to CC for calc 3, and it's just multivariable, series were covered in calc 2
>never ever learned anything about series

How fucked am I if I want to take ODE and Optimization?

I wished my lecturers had been more explicit about what these things are. "We're assigning meaning to what an infinite sum could be", rather than just jumping in and acting like an infinite sum is a natural consequence of basic finite sums and going "YEAH BRO YOURE JUST ADDING INFINITELY MANY TERMS"

>>8489360
you only need power series and the book covers the material

just watch a few khan or patrickjmt vids on the subject

>>8489114
They're actually pretty easy once you get used to them. My advice is write out each theorem/definition rigorously (using set theory and symbolic logic). This way you will know precisely what conditions must be true to use a given technique. You should be doing this from here out in your mathematics studies.