Vector Addition Homework: Multiplying Vectors & Gaussian Elimination

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g.lemaitre
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Homework Statement


Screenshot2012-07-14at25427AM.png

Homework Equations


The Attempt at a Solution


Do you see how 1 1 1 changes to 3 3 3. i know why gaussian elimination you can change any vector by multiplying it by anything you want. but for some reason i have difficulty believing that you're allowed to do that here. is that what they're doing? just multiplying that vector by 3 so as to facilitate the arithmetic. Or maybe they're multiplying both vectors by 3, so as to get rid of the 1/3, but that doesn't explain how the 1/3 gets on the left side of the parentheses.
 
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(1 1 1) = ([itex]\frac{3}{3}[/itex] [itex]\frac{3}{3}[/itex] [itex]\frac{3}{3}) =[/itex][itex]\frac{1}{3}[/itex](3 3 3)