Question 204880:  Hi all, I am having some trouble with vectors at the moment, I was hoping someone could show me how to do the following problems correctly. 
a) Find the distance between (2, -3, 1) and (-1, 0, -3) 
b) Find the maginitude of the vector ~w = 2~i - ~j + 4~k. (The ~ symbols represent an arrow above the values in the positive direction, I didnt know how to express this properly) 
Any help would be great,  
Thanks, -Nick. 
 Answer by Alan3354(69443)      (Show Source): 
You can  put this solution on YOUR website! a) Find the distance between (2, -3, 1) and (-1, 0, -3) 
It's the sqrt of the sum of the squares of the differences, dx, dy and dz 
d^2 = 3^2 + 3^2 + 4^2 = 9+9+16 
d^2 = 34 
d = sqrt(34) 
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b) Find the maginitude of the vector ~w = 2~i - ~j + 4~k. (The ~ symbols represent an arrow above the values in the positive direction, I didnt know how to express this properly) 
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Mag = the sqrt of the sum of the squares. 
r = sqrt(4 + 1 + 16) 
r = sqrt(21) 
r is the distance from the Origin to the endpoint of the vector. 
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