Valhalla Legends Archive

So how do americans multiply


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? What's your trick?

Quote from: Adron on December 18, 2003, 05:41 PM
So how do americans multiply

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            [a b c]      [p]
[x y z]  *  [d e f]   *   [q]
            [g h i]      [r]



? What's your trick?

TI-83+

And what does that say about the problem?

Quote from: Adron on December 18, 2003, 06:01 PM
And what does that say about the problem?

That it's a matrix multiplication problem?

I thought you'd be able to figure that out without asking your TI-83+?

 

Quote from: Adron on December 18, 2003, 06:56 PM
I thought you'd be able to figure that out without asking your TI-83+?

Americans must have super calculators now days which requires students to do no thinking.

Quote from: Spht on December 18, 2003, 09:36 PM

Quote from: Adron on December 18, 2003, 06:56 PM
I thought you'd be able to figure that out without asking your TI-83+?

Americans must have super calculators now days which requires students to do no thinking.

We have to learn how to turn them on.

Ugh you TI-83+ dummies. Adron showed a first-degree two-vector polynomial in matrix form. You should recognize that for what it is:
axp + bxq + cxr + dyp + eyq + fyr + gzp + hzq + izr

Edit: "Two-vector" instead of "two-variable", there are 6 variables.

Hehe, that was exactly what I wanted him to show

Complain to my teacher, she said you'll never have to deal with that without using the calculator.  

Quote from: hismajesty on December 19, 2003, 08:14 AM
Complain to my teacher, she said you'll never have to deal with that without using the calculator.  

She must not think very highly of her students...

Ah but what gets me is that we can't use calculators on the test. So instead of teaching us the way to do it without one she didn't include it on the test earlier this year.  

Quote from: hismajesty on December 17, 2003, 06:47 PM
1) I've noticed that in a few example problems my teacher did while getting factors from zeros of a paraballa's(sp?) curve that they have been the exact opposite. (example: Zeros of the function are (-1,0) & (5,0) while the factors are (X-5) & (X+1) is this always the case?

Yeah, I'm a little late, but anyway, the reason it's like this is the zeroes are what you have to add to the factor to get 0.  
So for the two examples, you would do this:
X - 5 = 0 --> x = 5
X + 1 = 0--> x = -1

Make sense?

Quote from: iago on December 19, 2003, 10:18 PM

Quote from: hismajesty on December 17, 2003, 06:47 PM
1) I've noticed that in a few example problems my teacher did while getting factors from zeros of a paraballa's(sp?) curve that they have been the exact opposite. (example: Zeros of the function are (-1,0) & (5,0) while the factors are (X-5) & (X+1) is this always the case?

Yeah, I'm a little late, but anyway, the reason it's like this is the zeroes are what you have to add to the factor to get 0.  
So for the two examples, you would do this:
X - 5 = 0 --> x = 5
X + 1 = 0--> x = -1

Make sense?

That works but actually it's because in the general form of the equation, the sign is negative, so all you have to do is reverse the sign. So (x-h) and (y-k) are the general form, and if you have (x-5) and (y+1) the 5 is positive, and the 1 is negative because a negative and a negative make a positive.