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Silvercord
05-05-2004, 07:18 PM
I just wanted everybody to know that I like calculus and that I feel a lot better about my existence knowing that no matter what happens, I can always do calculus.

If you don't like calculus you are a stupid moron loser dooty head crappy turd eater

scrappy
05-05-2004, 07:26 PM
I like calculus too! In fact, I like math in general. I like it so much that I'm on the math team!

Silvercord
05-05-2004, 07:31 PM
what are you some kind of a dork or something?

haha just kidding


:)

unanimous
05-05-2004, 07:36 PM
So far I love Pre-Calc, I'm taking Calculus and Statistics and as long as the current teacher leaves, I'll probably love Calc too. Silvercord, next year you wanna do my homework? By that I mean you're going to do it..or else!!

Silvercord
05-05-2004, 07:37 PM
sure thing :)

Silvercord
05-05-2004, 07:42 PM
I have been reading up on doing calculus IN 3D USING PARAMETRIC EQUATIONS... that's totally sweet. What I mean is coming up with ridiculously complex (but neat looking) equations for x,y, and z of t and then finding their a) volumes and b) surfaces areas of revolution, as well as the lengths of curves (i.e in the back of the book it proves how to find the length of a cork screw, i.e like the railgun in quake2).

this stuff is totally sweet

DavidP
05-05-2004, 08:32 PM
I like Calculus but I hate my Calculus teacher with a passion. If you ever go to BYU, take Calculus from any other teacher than Dr. Skarda. Just a tip for anyone who ends up going there.

axon
05-05-2004, 09:02 PM
I share DavidP's opinion, calc1 was OK but the prof sucked...calc2 was way easier than 1 and my prof was cool...calc 3 was the easiest and the coolest....yey for number theory next sem! .....

Silvercord
05-05-2004, 10:04 PM
what kinds of problems do you do in Calc3?

MrWizard
05-05-2004, 10:48 PM
Lost my post :(

Here is a quick review of my lost post:

Calculus III: [Multivariable Calculus]

Normal topics of coverage:

*Analytic geometry: vector algebra stuff
*Partial derivatives
*Multiple integrals
*Vector calculus: Green's theorem, Stoke's theoerm, surface integrals, divergence.

It really depends on what you learned in Calc I & II. Normally, the core stuff is the same though.

Axon:

Good luck with number theory buddy, it's a beast.

kashikoi
05-06-2004, 03:07 AM
number theory is great. so amazing that you can discover all sorts of complex patterns and theories from something as "simple" as numbers. and yes, calculus rocks.

EvBladeRunnervE
05-06-2004, 03:34 PM
I too am loving every bit of calculus, but do to my academic advisor I got screwed out of being able to take Calc II next semester, so I am going to have to wait for a semester before I can take it(I really wanted to bash his skull in, because he would not unlock me for registration even after I had told him I know exactly what I need/want to do, and do not need his help in course selection). I am planning on teaching my self calc II over the summer pretty much.

Lurker
05-06-2004, 03:59 PM
I'm taking as much calculus as I can...but I haven't really learned any yet.

Zach L.
05-06-2004, 04:07 PM
It's all about the abtract algebra. :D

holden
05-06-2004, 05:02 PM
Calc is awesome, I just took the calculus AB AP test, and I'm pretty sure I got a 4 or a 5...oh wait I'm not supposed to talk about that lol

Next semester for my senior high year, I get to take Calc II!!!! YEEEAHHHH!!!!

Oh and btw, I keep getting the wrong answer for the integral of (x)(e^2x)

Can anyone show me how to do that one?

gcn_zelda
05-06-2004, 05:38 PM
I like Calculus but I hate my Calculus teacher with a passion. If you ever go to BYU, take Calculus from any other teacher than Dr. Skarda. Just a tip for anyone who ends up going there.
Thanks for the tip :P

I'm only in Algebra II, but, I've got three more years in high school...

How many calculus courses are there? I know our high school offers AP Calc I and II, both of which I'll be taking, but how many more are there?

axon
05-06-2004, 07:14 PM
holden, taking calc in highschool is the smartest move you can do....in college its one of the fail courses and what you did in a year is done in a semester in college - so take advantage of the time length and get a good grade in calc 2

Zach L.
05-06-2004, 07:34 PM
Holden, use integration by parts. Let u = x, and dv = e^(2x)*dx

scrappy
05-06-2004, 08:03 PM
Calc is awesome, I just took the calculus AB AP test, and I'm pretty sure I got a 4 or a 5...oh wait I'm not supposed to talk about that lol

Next semester for my senior high year, I get to take Calc II!!!! YEEEAHHHH!!!!

Oh and btw, I keep getting the wrong answer for the integral of (x)(e^2x)

Can anyone show me how to do that one?

Here's what I did...

u = e^2x
du = 2e^2x dx
x = 1/2 * ln|u|

so... (S is the integral symbol)

S (x * e^2x) dx

1/2 S (2x * e^2x) dx

1/2 S (1/2 * ln|u|) du

1/4 S (ln|u|) du

1/4 (u * ln|u| - u + C)

1/4 (e^2x * ln|e^2x| - e^2x + C)

1/4 (e^2x * 2x - e^2x + C)

x/2 * e^2x - e^2x + C

Hmm.. I think I did that right :/

holden
05-06-2004, 08:33 PM
ah yes, im so stupid sometimes....

i was doing u=e^2x...

actually, heres the answer (and its correct)

S x * e^2x

u = x

du = 1 dx

du = dx (this is where the x goes out w00t)

dv = e^2x

v = e^2x / 2

vu - S v du , so:

(x * e^2x) / 2 - S e^2x / 2

((x * e^2x) / 2) - (e^2x / 4)

and finally:

(2x * e^2x - e^2x) / 4

And I checked it on my buddy (TI-83 Plus)

holden
05-06-2004, 08:37 PM
Oh and another question...integration by parts works fine, but is it possible to solve with straight up u substitution?

I couldn't get an x to cancel out with just a u substitution (which is all we learned, I learned integration by parts with this book my calc teacher lent me)

Silvercord
05-06-2004, 08:59 PM
I hate to say it but my high school calculus class hasn't even covered substitution by parts. I've read ahead and can do it myself, but my class is just retarded. I should've taken AP calc, I would've done well, but oh well.

DavidP
05-06-2004, 09:34 PM
i love integration by parts...it's like my favorite part of calculus...

Silvercord
05-07-2004, 06:10 PM
I have an incredibly easy time knowing the "right stuff to do" in order to get really really freaking high grades in calculus, but, like, I want to understand things at a really fundamental level. I always want to read *every* proof and memorize it and understand why it works and know how to derive it in my sleep. I've even got sick of not knowing how sqrt, sine and cosine works on my ti83 so I read how to do it and programmed my own sqrt sine and cosine functions! I admit however that for things like product rule and quotient rule I just memorized, but that's obsolete now that we're doing ln differentiation. I am a pain in the ass to teach, because every 30 seconds while my teacher is talking I'm like "explain that again" .

so, like, I think I read somewhere that zach is going to mit. is that true? If so, that's really freaking awesome. What kind of stuff are you guys doing? I want to be in really really really hard classes next year and if I'm not I'm going to drop out or kill everyone.

EDIT: when I said 'what stuff are you guys doing' I was kind of asking everybody that thinks they are in a fairly high level math course.

Silvercord
05-07-2004, 06:27 PM
Here's a program I wrote earlier in the year for one of our portfolios. What it does is you enter a script file defining a polynomial equation (doesn't work transcendental equations), enter the limits of integration, then enter the number of subdivisions, and estimates the value of the interal and the length of the curve numerically and it draws the function.

You have to adjust the camera position using the arrow keys to move around and the + and - to move in and out.

You must hit 'A' to tell the program what script file to open. I included a few to show how the syntax works. It's not overly useful because it's so easy to find the value of integrals with polynomials but oh well, this was more than expected for a high school class.

PedroTuga
05-07-2004, 11:04 PM
Multivariable integral or diferential calculus are nice, i like them, maths are my big passion (after my girl).
I wish i could have more maths courses... unfortunatly i complete all of them two years ago
let me just try that primitive...looks like a two-part primitive...

Vasant56
05-08-2004, 07:55 AM
http://www.calc101.com/


This site helps me out so much with derivatives. It does integrals, too.

Zach L.
05-08-2004, 11:30 PM
Silvercord, you heard correctly. :) It really is gonna be awesome.

I've always thought that the abstract algebra is quite fun. Granted, it doesn't have too many direct practical applications, but the idea of abstracting classes of numbers into various sets (of anything) and operations upon sets is quite fascinating. The neatest proof that I have seen in algebra (and the reason the theory was developed anyways) is the proof that not all roots of polynomials of degree five or more can be expressed in terms of radicals.

Shadow12345
05-09-2004, 07:19 AM
Zach have you dealt with Inertia tensors a lot? I need help. I'm working on implementing torque for a 3D engine, such that when objects touch linear and angular impulses are generated (I've got linear impulses, that was fairly easy, and it takes into account estimated coefficients of restitution, oh yeah baby!). It's easy when doing torque in 2D because the inertia tensor reduces to a scalar, but, in 3D it is a freaking 3x3 matrix or a quaternion, and like, I don't get it, lol.

EDIT:
Im silvercord

DavidP
05-09-2004, 09:19 AM
I have an incredibly easy time knowing the "right stuff to do" in order to get really really freaking high grades in calculus, but, like, I want to understand things at a really fundamental level. I always want to read *every* proof and memorize it and understand why it works and know how to derive it in my sleep. I've even got sick of not knowing how sqrt, sine and cosine works on my ti83 so I read how to do it and programmed my own sqrt sine and cosine functions!


I can sympathize with you on wanting to program your own sin, cos, and sqrt functions, because I have often wanted to do that myself. In fact, I have wanted to do that since before I even knew what sin and cos were. I remember asking my teacher what sin and cos were, and she told me the whole jibe about how they are ratios between the opposite, hypotenuse, adjacent and all that jazz, and I just responded: "So then what are they? What goes on inside them? They are functions, just like in programming, something goes on inside them. What goes on inside those functions?" And my teacher would just look back at me with a blank stare. Then I learned Calculus and Taylor Series...and now I can program my own!

But on another note: proofs? ugh. davidp does not enjoy proofs.

Shadow12345
05-10-2004, 09:32 AM
Okay, I dont' like the type of proof that is presented on a test like "prove this incredibly complex formula". I like *reading* the proofs and understanding *why* they work, but I don't like them on tests.

I mean, come on david, somebody like you, a computer scientist, must enjoy knowing how things work "under the hood", right?

KneeGrow
05-10-2004, 07:15 PM
Okay u learn a proof once, just understand how it works, then turn to the shortcut. No one uses the long way of limits to find a derivative. intstead power rule wow x^3 -> 3x^2.

However, volumes, area, surface area, and cross-sections are hard to understand if u dont see them visually. It helps if the teacher explains what the 2PI and PI really mean etc

Shadow12345
05-10-2004, 08:10 PM
well we all know where the 2PI comes from, but I actually don't know where PIr^2 comes from. So what I said was just an idea. and of course nobody uses the long form of derivatives all of the time, but it's nice to have at least seen where it comes from.

Zach L.
05-10-2004, 09:09 PM
Silvercord, I haven't done a lot with tensors (and its really been a while since I did do anything), but I'll certainly try to help if I can.

As a side note, my favorite reference on tensors is Vector & Tensor Analysis with Applications by Borisenko and Tarapov (and it's one of those nice little Dover books too).

Silvercord
05-11-2004, 07:38 PM
Hey Zach buddy, I am going to do some more reading before I ask anything. I can hopefully figure it out. Is that like, an ebook, or an actual book book all about tensors?

I like, just learned last week that tensors aren't vectors...lol so yeah.