What is the span of {(1; 1; 0),(0; 0; 2)}?

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Homework Statement



What is the span of {(1; 1; 0),(0; 0; 2)}?




The Attempt at a Solution



So the span is λ1(1; 1; 0) + λ2(0; 0; 2)

But how should I express my answer?
The given answer on the sheet is as below:
The span is {( λ,λ,β )|λ,βεR}
 
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negation said:

Homework Statement



What is the span of {(1; 1; 0),(0; 0; 2)}?




The Attempt at a Solution



So the span is λ1(1; 1; 0) + λ2(0; 0; 2)
The span is all linear combinations of <1, 1, 0> and <0, 0, 2>, which is the same span as all linear combinations of <1, 1, 0> and <0, 0, 1>.

Using the same letters as in the answer, the span is all vectors of the form λ<1, 1, 0> + β<0, 0, 1> = <λ, λ, 0> + <0, 0, β>, or more simply, <λ, λ, β>, with λ and β arbitrary reals.
negation said:
But how should I express my answer?
The given answer on the sheet is as below:
The span is {( λ,λ,β )|λ,βεR}
 
Mark44 said:
The span is all linear combinations of <1, 1, 0> and <0, 0, 2>, which is the same span as all linear combinations of <1, 1, 0> and <0, 0, 1>.

Using the same letters as in the answer, the span is all vectors of the form λ<1, 1, 0> + β<0, 0, 1> = <λ, λ, 0> + <0, 0, β>, or more simply, <λ, λ, β>, with λ and β arbitrary reals.

In red, where did <0,0,1> came from? 2<0,0,1> = <0,0,2>?

Edit: Alright, let's not complicate things since my intention was only to know why the answer was expressed in the way it was.
Thanks
 
Last edited:
negation said:
In red, where did <0,0,1> came from? 2<0,0,1> = <0,0,2>?
Yes, <0, 0, 2> is a scalar multiple of <0, 0, 1>. You could just as well have picked <0, 0, 17>.
negation said:
Edit: Alright, let's not complicate things since my intention was only to know why the answer was expressed in the way it was.
Thanks
 
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