What is the meaning of T(1), T(x), and T(x2) in polynomial transformations?

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The discussion revolves around understanding polynomial transformations T(1), T(x), and T(x^2) in the context of linear algebra. The user expresses confusion about the notation and the separate representations of polynomial transformations, seeking clarification on their meanings. It is noted that these transformations can be expressed as a linear combination of their outputs when applied to a general polynomial. Additionally, users report issues with the forum's math symbol preview function, indicating it has been malfunctioning for some time. The conversation concludes with a suggestion to post such questions in a more appropriate section, as they pertain to advanced topics beyond precalculus.
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Homework Statement



T: R3[x] R3[x] // for some reason the arrow symbol isn't working! When I do the arrow it previews as the third power for some reason. Also, whenever I preview post, it adds 1 2 b[3] again for some reason and I have to delete those lines every time...a bit fustrating...

T(1) = 3 + 2x +4X2
T(x) = 2 + 2x2
T(x2) = 4 + 2x 3x2

Find all eigenvalues and their linear subspaces they create.

The Attempt at a Solution



I don't exactly understand what to do here. I am used to transformations from R3 to R3, not the polynomial transformations. And I am a bit confused how they wrote T(1) T(x) and T(x2) separately. Is that the way you write the transformations for polynomials? I thought it should be like this: T(alpha0 + alpha1x + alpha2x2) = (...)

I guess I just need someone to explain what

T(1) = 3 + 2x +4X2
T(x) = 2 + 2x2
T(x2) = 4 + 2x 3x2

means.

Thanks.
 
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T(1) = 3 + 2x + 4X^2
T(x) = 2 + 2x2
T(x^2) = 4 + 2x+ 3x^2

since they are linear:
T(a_1+a_2x+a_3x^2)=(a_1(3 + 2x + 4X^2) + a_2 (2 + 2x2) + a_3 (4 + 2x+ 3x^2))
 
Thanks. I solved the question.

By the way, anybody have an idea why the math symbols are behaving strangely? Is this happening to anybody else?
 
Like this?
T:R^3 \to R

Click the expression to see the LaTeX I used.

The preview function has not been working correctly for about the past month. Instead of showing you a preview of what you have typed, it seems to take whatever is in cached memory and displays that.

Also, for future reference, problems like this should be posted in the Calculus & Beyond section. Eigenvalues are definitely not at the Precalc level.
 
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