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Poll
6 x 8 = ?
Zero 11%
Nothing 11%
All of the above 0%
All of the below 77%

Votes: 18

 I've had enough of this Enlightement crap

 Author:  Topic:  Posted:
Mar 10, 2002
 Comments:
It's time to cancel Mathematics.
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Trolling for Baby Jesus, huh? (none / 0) (#1)
by tkatchev on Sun Mar 10th, 2002 at 05:38:49 AM PST
Although in all honesty, I agree with you. Mathematics is a complete sham.


--
Peace and much love...




 
Umm... (none / 0) (#2)
by jvance on Sun Mar 10th, 2002 at 09:00:28 AM PST
I don't think you can derive a cross product from two simple scalars.
--
Adequacy has turned into a cesspool consisting of ... blubbering, superstitious fools arguing with smug, pseudointellectual assholes. -AR

WTH? (none / 0) (#3)
by tkatchev on Sun Mar 10th, 2002 at 09:34:26 AM PST
I don't think you have the first clue what you're talking about.

(P.S. How do you "derive" a scalar?)


--
Peace and much love...




Unfortunate choice of term (none / 0) (#4)
by jvance on Sun Mar 10th, 2002 at 10:48:31 AM PST
I should have said "calculate." Seriously, how the hell am I supposed to calculate a cross product when all I'm given are scalars?

6 x 8 = 6 * 8 * |sin theta|. (where * represents scalar multiplication. Stupid keyboard.)

Where's theta? I don't see any theta! Where's the direction component of the vectors? perhaps they disappeared first when Mathematics was cancelled.

--
Adequacy has turned into a cesspool consisting of ... blubbering, superstitious fools arguing with smug, pseudointellectual assholes. -AR

Silly question. (none / 0) (#5)
by tkatchev on Sun Mar 10th, 2002 at 11:14:53 AM PST
Although the serious answer would be that a cross-product of two scalar "vectors" would always be 0, by definition; this is because all vectors in R**1 are collinear, and the cross-product of any two linearly dependent vectors is 0 by definition.

If this makes little sense to you, you can think of a vector in R**1 as a ray from 0 on the number line; in that case, the angle between any such two vectors is 0, and sin(0) is 0.

Although such a mode of thinking is very bad and unmathematical; mathematicians, as a rule, believe in the primacy of linear algebra over real-world empirical observations.


--
Peace and much love...




OK (none / 0) (#6)
by jvance on Sun Mar 10th, 2002 at 12:53:30 PM PST
So think of it as:

|i j k|
|6 0 0|
|8 0 0|


It didn't appear implicit in the equation to me, but then I'm not a mathematician.
--
Adequacy has turned into a cesspool consisting of ... blubbering, superstitious fools arguing with smug, pseudointellectual assholes. -AR

That's a bad way of reaching the solution. (none / 0) (#7)
by tkatchev on Sun Mar 10th, 2002 at 01:33:30 PM PST
The 3x3 determinant trick is just a special case for when you want to calculate a cross-product in R**3. The actual definition says nothing about a determinant -- it merely states that |[A, B]| is equal to |A| |B| sin(A^B), and that the resulting vector points in a direction perpendicular to both A and B, according to the "right hand rule".

From this definition we can deduce that for two linearly-dependent vectors the cross-product is equal to zero. (We can think of this fact as just a part of the definition, but who cares...)

We know from linear algebra that two vectors are linearly dependent if the determinant of their respective column-matrix is equal to zero. Since in our case the respective matrix isn't even square we can be sure that the matrix is linearly dependent. (But note that you don't need to calculate determinants to figure out that two vectors in R**1 are linearly dependent; that's pretty obvious anyways, isn't it?)

What you did was to project vectors in R**1 onto vectors in R**3 and then calculated the respective cross-product -- which is not in fact justified! First of all, the way you simply picked any old arbitrary way of projecting vectors onto a basis of a different dimension was not very honest -- stricly speaking, the two vectors are in different linear spaces, and may or may not be related by weird correlations. Second of all, you still have to prove that linear dependence in R**1 implies linear dependence in R**3.

All in all, I think you need to get rid of the bad habit of using ready-made algorithms in math. But, that seems to be the global disease of the American education system...


--
Peace and much love...




W00t (none / 0) (#8)
by JoePain on Sun Mar 10th, 2002 at 10:00:52 PM PST
Dey don let us tink cuz we spozed to jus bye stuff. We like spend mony. We be conSumas. Dey tak r brains out when we just lil kids so we don hav to tink jus act. Tinking bad for cuntry. Spend Spend Spend. Dis way we no undastan dat we be sheeps. I hear dis cald properganda, but I no not wat properganda is. I tink it to keep rich rich.

Me like job spend money bye stuff.


Dear Lunix user (none / 0) (#10)
by opivy on Mon Mar 11th, 2002 at 07:11:33 AM PST
Are you mocking the issue that is on the front page with your mock Ebonics?


"It's not the people who vote that count: only the people that count the votes" - Joseph Stalin

I love tha irony. (none / 0) (#11)
by elenchos on Mon Mar 11th, 2002 at 08:33:30 PM PST
Man think he smart but BAE grammar too hard for his fool self? I'm serious...


I do, I do, I do
--Bikini Kill


no kidding (none / 0) (#12)
by nathan on Tue Mar 12th, 2002 at 07:06:30 AM PST
This Lunix user is such a racist jerk that he apparently think BAE is just SWE with a hick accent, bad grammar, and a debased vocabulary.

Who'd have thought the front-page article would be this accurate? It is truly a journalistic coup for Adequacy.org.

Nathan
--
Li'l Sis: Yo, that's a real grey area. Even by my lax standards.

 
Right, (none / 0) (#9)
by jvance on Sun Mar 10th, 2002 at 11:16:57 PM PST
but give me a break, will ya? I took Vector Calculus a decade ago, and haven't used the stuff since. The most advanced math I've done lately was used to figure out how to cut the Hardibacker board for my bathroom floor today.

You would have enjoyed my Vector Calculus class. The midterm and final exams were identical, consisting of one question: explain what you have learned in this class thus far and why it is important. You have one hour.


--
Adequacy has turned into a cesspool consisting of ... blubbering, superstitious fools arguing with smug, pseudointellectual assholes. -AR

 

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