Finding Coordinate Matrix for Linear Transformation T

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SUMMARY

The discussion centers on finding the coordinate matrix [T]FF for the linear transformation T defined from V = P2 to W = P2. The transformation is given by T(a0 + a1t + a2t^2) = (2a0 + 4a1 + 2a2) + (2a0 + 3a1 + 4a2)t + (−2a0 + 3a1 + 4a2)t^2. The ordered basis F consists of f1(t) = 1, f2(t) = 1 + t, and f3(t) = 1 + t + t^2. The correct approach involves calculating T(f1(t)), T(f2(t)), and T(f3(t)) to derive the matrix representation of T relative to the basis F.

PREREQUISITES
  • Understanding of linear transformations and their representations.
  • Familiarity with polynomial spaces, specifically P2.
  • Knowledge of basis vectors and coordinate matrices.
  • Ability to perform polynomial arithmetic and coefficient extraction.
NEXT STEPS
  • Calculate the coordinate matrix for different linear transformations in polynomial spaces.
  • Explore the properties of linear transformations and their matrix representations.
  • Study the relationship between different bases in vector spaces.
  • Learn about the implications of changing bases on matrix representations.
USEFUL FOR

Students studying linear algebra, particularly those focusing on linear transformations and polynomial vector spaces. This discussion is beneficial for anyone looking to deepen their understanding of coordinate matrices and basis transformations.

Rifscape
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Homework Statement


Hey, I posted another question yesterday, and thanks to the kindness and brilliance of hall of ivy, I was able to solve it. However when I apply the same logic to this new question I cannot seem to get it, can someone explain or show me how to do this question.

Consider the linear transformation T from
V = P2
to
W = P2
given by
T(a0 + a1t + a2t^2) = (2a0 + 4a1 + 2a2) + (2a0 + 3a1 + 4a2)t + (−2a0 + 3a1 + 4a2)t^2
Let F = (f1, f2, f3) be the ordered basis in P2 given by f1(t) = 1, f2(t) = 1 + t, f3(t) = 1 + t + t^2
Find the coordinate matrix [T]FF
of T relative to the ordered basis F used in both V and W, that is, fill in the blanks below: (Any entry that is a fraction should be entered as a proper fraction, i.e. as either x/y or -x/y where x and y are positive integers with no factors in common.)
T(f1(t)) = _f1(t) + _f2(t) + _f3(t)
T(f2(t)) = _f1(t) + _f2(t) + _f3(t)
T(f3(t)) = f1(t) + f2(t) + f3(t)
and therefore :
[T]FF
= the matrix created by the coefficients of the answers above

Homework Equations


Basis equation.

The Attempt at a Solution


I tried doing what I did for the previous question. Since f1(t) = 1. It is 1 + 0t + 0t^2 = 1. So when I plugged in this to the T(a0 + a1t + a2t^2) I got 2 + 2t - 2t^2 for the coefficients of the first matrix. However when I enter this answer in, it is wrong except for the -2 coefficient for t^2. I have no idea why. I think it has something to do with how f2(t) is 1 + t, and how f2(t) is 1 + t + t^2. Could someone please help me on this?

Thank you for your time.
 
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Rifscape said:

Homework Statement


Hey, I posted another question yesterday, and thanks to the kindness and brilliance of hall of ivy, I was able to solve it. However when I apply the same logic to this new question I cannot seem to get it, can someone explain or show me how to do this question.

Consider the linear transformation T from
V = P2
to
W = P2
given by
T(a0 + a1t + a2t^2) = (2a0 + 4a1 + 2a2) + (2a0 + 3a1 + 4a2)t + (−2a0 + 3a1 + 4a2)t^2
Let F = (f1, f2, f3) be the ordered basis in P2 given by f1(t) = 1, f2(t) = 1 + t, f3(t) = 1 + t + t^2
Find the coordinate matrix [T]FF
of T relative to the ordered basis F used in both V and W, that is, fill in the blanks below: (Any entry that is a fraction should be entered as a proper fraction, i.e. as either x/y or -x/y where x and y are positive integers with no factors in common.)
T(f1(t)) = _f1(t) + _f2(t) + _f3(t)
T(f2(t)) = _f1(t) + _f2(t) + _f3(t)
T(f3(t)) = f1(t) + f2(t) + f3(t)
and therefore :
[T]FF
= the matrix created by the coefficients of the answers above

Homework Equations


Basis equation.

The Attempt at a Solution


I tried doing what I did for the previous question. Since f1(t) = 1. It is 1 + 0t + 0t^2 = 1. So when I plugged in this to the T(a0 + a1t + a2t^2) I got 2 + 2t - 2t^2 for the coefficients of the first matrix.
This is not the "first matrix." This is ##T(f_1)##, the first column of a matrix representation of T. Now calculate ##T(f_2)## and ##T(f_3)##, which will be, respectively, the 2nd and 3rd columns of your matrix.

This matrix won't be the answer, as those three column vectors are in terms of the standard basis ({1, t, t2}), not the basis of this problem.
Rifscape said:
However when I enter this answer in, it is wrong except for the -2 coefficient for t^2. I have no idea why. I think it has something to do with how f2(t) is 1 + t, and how f2(t) is 1 + t + t^2. Could someone please help me on this?

Thank you for your time.
 

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