Bases for Vector Space V=\mathbb{R}^3

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In summary, the only set that is not a basis for the vector space V=R3 is set (b), as it is not linearly independent and does not span V. The other three sets (a), (c), and (d) are all bases for V.
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Ted123
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Homework Statement



Which of the following sets [itex]S[/itex] are bases for the vector space [itex]V=\mathbb{R}^3[/itex]?

(a) [itex]S=\left\{ \begin{bmatrix} 1 \\ 1 \\ 0 \end{bmatrix} , \begin{bmatrix} 1 \\ 0 \\ 0 \end{bmatrix} , \begin{bmatrix} 1 \\ 1 \\ 1 \end{bmatrix} \right\}[/itex]

(b) [itex]S=\left\{ \begin{bmatrix} 1 \\ 1 \\ 0 \end{bmatrix} , \begin{bmatrix} 0 \\ 0 \\ 1 \end{bmatrix} , \begin{bmatrix} 1 \\ 1 \\ 1 \end{bmatrix} \right\}[/itex]

(c) [itex]S=\left\{ \begin{bmatrix} 1 \\ 1 \\ 0 \end{bmatrix} , \begin{bmatrix} 0 \\ 0 \\ 1 \end{bmatrix} , \begin{bmatrix} 1 \\ -1 \\ 1 \end{bmatrix} \right\}[/itex]

(d) [itex]S=\left\{ \begin{bmatrix} 1 \\ -1 \\ 1 \end{bmatrix} , \begin{bmatrix} 1 \\ 1 \\ -1 \end{bmatrix} , \begin{bmatrix} -1 \\ 1 \\ 1 \end{bmatrix} \right\}[/itex]

The Attempt at a Solution



By my reckoning, the only set that isn't a basis is (b) as it isn't linearly independent and [itex]\text{Span}(S)\neq V[/itex]. Correct?
 
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  • #2
Since there are only 3 and the dimension of R3 is 3, you are correct that whether or not they are linearly independent determines whether they are a spanning set (basis).
 

FAQ: Bases for Vector Space V=\mathbb{R}^3

What is a vector space?

A vector space is a mathematical structure that consists of a set of objects called vectors, and a set of operations that can be performed on these vectors. In the case of V=\mathbb{R}^3, the vectors represent three-dimensional points in space and the operations include addition and scalar multiplication.

What does V=\mathbb{R}^3 mean?

V=\mathbb{R}^3 is a notation that represents a vector space with three dimensions, where the vectors are elements of the set of real numbers, \mathbb{R}. This means that each vector in this space has three components, and these components can take on any real number value.

What are the properties of a vector space?

A vector space must satisfy certain properties, including closure under addition and scalar multiplication, existence of an additive identity (zero vector), and existence of additive inverses. It also must follow the commutative, associative, and distributive laws. These properties ensure that the vector space is well-defined and consistent.

How is a basis for a vector space determined?

A basis for a vector space is a set of vectors that span the entire space and are linearly independent. This means that any vector in the space can be written as a linear combination of the basis vectors, and no basis vector can be expressed as a linear combination of the others. In the case of V=\mathbb{R}^3, a common basis is \{\mathbf{i}, \mathbf{j}, \mathbf{k}\}, where \mathbf{i}, \mathbf{j}, \mathbf{k} are unit vectors in the x, y, and z directions, respectively.

Can a vector space have more than one basis?

Yes, a vector space can have multiple bases. In fact, any set of linearly independent vectors that span the space can be considered a basis. In the case of V=\mathbb{R}^3, other possible bases include \{\mathbf{u}, \mathbf{v}, \mathbf{w}\}, where \mathbf{u}, \mathbf{v}, \mathbf{w} are any three non-coplanar vectors in the space.

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