
#1
Jun3005, 04:30 AM

P: 322

I'm stuck on the following problem:
Describe the span of the vectors u1 and u2 in R^3, where u1 = (1, 1, 1), u2 = (1, −1, 1) I know that the span is a(u1)+b(u2), which becomes (a+b,ab,a+b), but I don't know where to go from here. TIA. 



#2
Jun3005, 12:06 PM

Sci Advisor
HW Helper
P: 9,422

do you know gaussian elimination, reduction for matrices?
i.e. how to solve for all vectors perpendicular to both of those? or you could just look at your general vector, since it satisfies an obvious equation. 



#3
Jun3005, 07:24 PM

HW Helper
P: 2,151

It will then be easier to see what is happening. 



#4
Jun3005, 09:55 PM

P: 322

span of vectors
Is it the xz plane in R^3?




#5
Jun3005, 09:58 PM

Sci Advisor
HW Helper
P: 9,422

have you noticed that the first and third entries of your vectors are equal? what does that tell you about an equations characterizing these vectors?




#6
Jun3005, 10:10 PM

P: 322

The main diagonal line in xz plane



Register to reply 
Related Discussions  
The dimension of the span of three linearly independent R^3 vectors  Calculus & Beyond Homework  6  
span of two vectors  Calculus & Beyond Homework  7  
LINEAR ALGEBRA: Find vectors that span the image of A...  Calculus & Beyond Homework  3  
span of a set of 3D vectors  Calculus & Beyond Homework  1  
Prove span(S1 U S2) = span(S1) + span(S2)  Calculus & Beyond Homework  10 