Anyone know any Calculus?

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Matthiasa

Diamond Member
May 4, 2009
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23
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I got 1, -sin a. I just derived it until it simplified out...

What about 2?

Really graph the first one, it will show what I said. (read how i answered it as well)


The other two i would just use Google to find a derivative solver, because of how long they would take.

They both use chain and product rule though.
 

ConstipatedVigilante

Diamond Member
Feb 22, 2006
7,670
1
0
Damnit, just took my exam and after I handed it in, I realized I forgot to do the 2nd part of a problem (finding the derivative at a point). I could have gotten ~5 points on that. Fuckstick.
 

ussfletcher

Platinum Member
Apr 16, 2005
2,569
2
81
I have a test on differential equations in the morning, any math pros want to take it for me?
 

vshah

Lifer
Sep 20, 2003
19,003
24
81
Alcohol and calculus don't mix. Never drink and derive.

damn, came here to post this.

also, no offense OP, but freak occurrences like this is why i trained myself in the latter years of college to always finish my hw as soon as it was assigned. you end up doing the same amount of work, but no stress about finishing. of course some people work much better under stress i suppose.
 

TridenT

Lifer
Sep 4, 2006
16,800
45
91
Can't help yah there. I forgot everything. :/ If you asked me two years ago I could have kicked its ass. :p
 

RapidSnail

Diamond Member
Apr 28, 2006
4,257
0
0
1: -sin(a)
3: -(pi*sin(sqrt(sin(pi*x)))cos(pi*x)cos(cos(sqrt(sin(pi*x))))sin(cos(sqrt(sin(pi*x)))))/sqrt(sin(pi*x))
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
Really graph the first one, it will show what I said. (read how i answered it as well)


The other two i would just use Google to find a derivative solver, because of how long they would take.

They both use chain and product rule though.

Product rule not found & I disagree with infinity/-infinity for the first one.
 
Mar 11, 2004
23,444
5,852
146
I never experienced a curve in my math classes.

I fucking hated college math courses. I remember taking a test and feeling good, getting it back and having like a 40 on it. I was just WTF? So I looked it over and there were like 3 problems that were worth like 60 points that I got correct, but I got marked for doing it the wrong way (did it how my high school calc teacher taught, not how they did it. I took it in, showed them that I didn't do it wrong, just different, the guy agreed but also said they wouldn't change the score. With the curve I ended up with like a 60-something. I was just like WTF. Sadly that wasn't even the most WTF test grading bullshit I experienced (which would interestingly enough include bigfoot and geology).
 

PieIsAwesome

Diamond Member
Feb 11, 2007
4,054
1
0
Because the first one is indeterminant(is that the right term?) you need to apply L'Hospital's rule (or however you spell that).

The other 2, just take the first derivative. Looks like you will at least need the chain rule, but the formatting in your post is so, ugh, that is all I am going to say.
 

PieIsAwesome

Diamond Member
Feb 11, 2007
4,054
1
0
I fucking hated college math courses. I remember taking a test and feeling good, getting it back and having like a 40 on it. I was just WTF? So I looked it over and there were like 3 problems that were worth like 60 points that I got correct, but I got marked for doing it the wrong way (did it how my high school calc teacher taught, not how they did it. I took it in, showed them that I didn't do it wrong, just different, the guy agreed but also said they wouldn't change the score. With the curve I ended up with like a 60-something. I was just like WTF. Sadly that wasn't even the most WTF test grading bullshit I experienced (which would interestingly enough include bigfoot and geology).

For some tests I have taken they specifically ask you to use methods learned in class. Or a problem tells you to use a specific method. On others, as long as you can prove and backup your answer, anything is fair game. If this wasn't the case for your test then that score is BS.
 

Red Squirrel

No Lifer
May 24, 2003
70,561
13,801
126
www.anyf.ca
calculus.jpg


That's all I know
 

Matthiasa

Diamond Member
May 4, 2009
5,755
23
81
Product rule not found & I disagree with infinity/-infinity for the first one.

As written it would have been 0 as fixed it's either + or - ∞.

You can graph it if you disagree. :p

Er just checked yeah no chain rule. Horrible formating.
 
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DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
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As written it would have been 0 as fixed it's either + or - ∞.

You can graph it if you disagree. :p

Er just checked yeah no chain rule. Horrible formating.

Could you explain why you think it's + or - ∞?
Here's a counter example of what I think you're using as a reason: what's the limit as x -> 0 of sin(x) / x ?
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
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And, his formatting is perfect. Nothing wrong with it at all. Well, almost perfect. There's an unnecessary set of parentheses around the first term on #2.
Then again, I guess that assumes he copied the problem correctly.
 
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Matthiasa

Diamond Member
May 4, 2009
5,755
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Could you explain why you think it's + or - ∞?
Here's a counter example of what I think you're using as a reason: what's the limit as x -> 0 of sin(x) / x ?


thats 1, but he is dividing by x^2 for the fix.

Oh well I read it wrong either way whats one extra check when he was doing it. If you can you do if you can't well go on for it. :(
 
Mar 11, 2004
23,444
5,852
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For some tests I have taken they specifically ask you to use methods learned in class. Or a problem tells you to use a specific method. On others, as long as you can prove and backup your answer, anything is fair game. If this wasn't the case for your test then that score is BS.

Yeah, no they didn't say anything specific. Just said show your work. After talking to them, they just said that's what the curve is for. I wasn't a fan of the grading (there were a bunch of cases of stuff even worse than mine, they always had people talking about the grading). I think at one point I got docked for showing the full work even (put in an extra unnecessary step that let me remember and think the problem through properly, and I lost like 2 points for it). I remember a quiz where 2 people in the class had the exact same answer and work, and one of them was marked wrong and the other correct, and the instructor wouldn't change the grade when they brought it up to him. It was fucked up.

The instructors were actually nice, but I got the impression that the people over them told them to never change grades so that they wouldn't get overwhelmed with people trying to get better grades. These were large classes (that were split into smaller but still 30-40 people recitations), so I could kinda see them doing that, but it would take a lot of complaints for them to do anything about their grading screwups.
 

fatpat268

Diamond Member
Jan 14, 2006
5,853
0
71
Can't help yah there. I forgot everything. :/ If you asked me two years ago I could have kicked its ass. :p

Yea, same here.

I still know the basics of deriving and integrating, but as soon as you throw some trig functions in there my mind goes blank.

Although, I'd probably figure it out if I tried, but I'm not interested in helping someone do their homework.