Linear Transformation / Coordinate Vector Question

So the solution would be c1 = -4, c2 = 8. In summary, the problem involves finding the coordinates of a vector relative to a given ordered basis of a subspace. The solution involves solving a system of equations with the basis vectors as the coefficients and the given vector as the solution.
  • #1
Gotejjeken
29
0

Homework Statement


The following vectors form an ordered basis E = [v1, v2] of the subspace V = span(v1,v2):

v1 = (1,2,1)^T , v2 = (3,2,1)^T.

The vector v = (24,-8,-4)^T belongs to the subspace V. Find its coordinates (c1,c2)^T = [v]E relative to the ordered basis E = [v1,v2].

Homework Equations



None.

The Attempt at a Solution



I am not quite sure how to approach this problem. I wanted to calculate the inverse of:

1 3
2 2
1 1

and then multiply v = (24, -8, -4)^T by the inverse to get the coordinate vector relative to E, however I have no idea if that is the right approach. I feel I'm missing something...
 
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  • #2
Gotejjeken said:

Homework Statement


The following vectors form an ordered basis E = [v1, v2] of the subspace V = span(v1,v2):

v1 = (1,2,1)^T , v2 = (3,2,1)^T.

The vector v = (24,-8,-4)^T belongs to the subspace V. Find its coordinates (c1,c2)^T = [v]E relative to the ordered basis E = [v1,v2].

Homework Equations



None.

The Attempt at a Solution



I am not quite sure how to approach this problem. I wanted to calculate the inverse of:

1 3
2 2
1 1
The only matrices that have inverses are square matrices. The one you show above is 3 x 2, so isn't square.
Gotejjeken said:
and then multiply v = (24, -8, -4)^T by the inverse to get the coordinate vector relative to E, however I have no idea if that is the right approach. I feel I'm missing something...

Solve the equation below for the constants c1 and c2.
(24, -8, -4)^T = c1*(1,2,1)^T + c2*(3,2,1)^T
 
  • #3
Oh, wow. Thank you, it seems I was over-complicating things...the wording of that problem had my brain in knots.
 

FAQ: Linear Transformation / Coordinate Vector Question

What is a linear transformation?

A linear transformation is a mathematical operation that maps one vector space to another, while preserving the linear structure and operations of the original space. It is often represented as a matrix multiplication and can be used to describe changes in geometric objects such as rotations, reflections, and scaling.

What is a coordinate vector?

A coordinate vector is a vector that represents the coordinates of a point in a specific coordinate system. It is usually represented as an ordered list of numbers and can be used to describe the position of a point in space or the direction and magnitude of a vector.

How do you perform a linear transformation on a coordinate vector?

To perform a linear transformation on a coordinate vector, you first need to represent the transformation as a matrix. Then, you multiply the coordinate vector by the transformation matrix to obtain the new coordinates of the vector in the transformed space.

What is the purpose of a linear transformation?

The purpose of a linear transformation is to describe and analyze changes in geometric objects in a mathematical and systematic way. It allows us to understand transformations in various contexts, such as in physics, computer graphics, and engineering.

How do you determine if a transformation is linear?

To determine if a transformation is linear, you can use the properties of linearity, which include preserving addition and scalar multiplication. In other words, if the transformation of the sum of two vectors is equal to the sum of the individual transformations, and the transformation of a scaled vector is equal to the scalar times the transformation of the original vector, then the transformation is linear.

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