<p>On page 3 of the PDF, on the line immediately the the right of the blue text on that page, they combined two summation expressions, but I don't know how.</p>
<p>It looks to me like they screwed up and didn't account for the different indices, but then again, there's no way they would have screwed up something so big (otherwise the entire second example would've been effed up, due to the wrong recursion formula). On the other other hand, it IS a supplementary chapter on their website, so it may not have been reviewed very thoroughly.</p>
<p>Oh.. I know what's up. The sum with n=1 would still equal the same thing even if n=0, because the partial sum at n=0 is zero. That's what they meant with the blue text.</p>
<p>Ohh, which was counterintuitive to me because what makes this case special is the hidden limit. Normally making sure the indices are equal is crucial in combining sums, but since in this case the sum was adding all the way to infinity, you can safely ignore the shifted index and keep the expression exactly the same. Shi---</p>
<p>why the **** are you replying to your own thread? if you know the answer, simply post "never mind. got it. thanks." and move on. no need to reply to your own post, write down a bunch of crap for the world to see, pretend you're smart, and be an immature little girl. if you're trying to impress some hot chick on CC, let me give you a little piece of advice: Calc 3 wouldn't be my tactic of choice.</p>
<p>I seriously had no clue what I was missing, and was ****ting my pants since I have an exam on this stuff in... well, now half an hour.</p>
<p>I honestly was hoping for someone to help. I realize that replying back in 9 minutes and saying exactly what I was looking for made this thread look like a staged brag thread, but I was racking my brains for every second in that time, and when I finally (surprisingly) got the answer on my own, I posted back in case anyone on CC might wonder in the future and so that no one else would waste their time on the problem.</p>
<p>Edit: Uhh.. okay, re-read your post. I posted the explanations because I was still thinking through and trying to formalize the unorganized mess of stuff in my head at the time. I'm OCD in that way. A huge reason I even posted here was because I thought I wouldn't be sounding like a pretentious a-hole for this stuff.</p>
<p>lol karch, you're cute. what does my username on an internet forum have ANYTHING to do with my character? am I the one posting diff eq's on an SAT PREP FORUM, only to have answered the question in a feeble attempt to sound educated? do you see me waving my hands frantically like a douchebag, trying to attract attention myself? no. </p>
<p>I'm no "fagg0t." I call it like I see it, and, damn, all i see is a pretentious prick who lacks the social dexterity to establish any -- uh, yeah. never mind. I'll leave it at that.</p>
<p>Hey, half these folks have taken Calc III, or at least that's what I've seen in the "What are my chances?" forum, and I frequent this forum most often. Where else would I be able to get a response in within half an hour?</p>
<p>But alas, I'm sorry you felt threatened, avant-garde. Have an e-cookie or something, because you're obviously a self-conscious f--- out to pick a fight.</p>
<p>again, your childish and non-sequitur remarks regarding my username are a blatant corroboration of your inability to prove a point. yes, i'm "avant-garde" on collegeconfidential. what's your point? </p>
<p>i'm not picking a fight at all. i simply stated that 'if you know the answer, simply post "never mind. got it. thanks." and move on.' that's the bottom line.</p>
<p>if you're such a gentleman, why do you keep replying to my posts? don't you have a test to take right now anyway?</p>
<p>Our school doesn't offer Calc III, but plenty of people post that they've taken it on the chances forum. You dual enroll at a community college to take it.</p>