Proving Boundedness of Operator T in L^p(-2,2)

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SUMMARY

The operator T defined as (Tf)(x) = f(x)x maps from L^p(-2,2) to L^p(-2,2) for natural numbers p ranging from 1 to infinity. The proof utilizes Hölder's inequality and substitution integrals to establish boundedness. The integral ∫_{-2}^{2} |f(x)x|^p dx is evaluated, demonstrating that the operator remains within the same space. The discussion concludes with a successful resolution of the problem through a substitution approach.

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Homework Statement


The operator T maps from [itex]L^p(-2,2)\rightarrow L^p(-2,2)[/itex] is defined [itex](Tf)(x) = f(x) x[/itex]
Show that the operator maps from L^p(-2,2) into the same.

Homework Equations


p is a natural from 1 to infinity.
Holders inequality
Substitution integrals

The Attempt at a Solution


I look at the following integral
[itex]\int\limits_{-2}^{2} |f(x)x|^pdx = \int\limits_{-2}^{2}|f(x)x|^{p-1}|f(x)x|dx\leq<br /> \int\limits_{-2}^{2} |f(x)x|^{p-1}\left[\left(\int\limits_{-2}^{2}|f(x)|^rdx\right)^{1/r}\left(\int\limits_{-2}^{2}|x|^qdx\right)^{1/q}\right] = \\<br /> ||f(x)||_p\int\limits_{-2}^{2} |f(x)x|^{p-1}\left[\left(\int\limits_{-2}^{2}|x|^qdx\right)^{1/q}\right][/itex]
And here I am stuck
Edit: maybe a substitution would do? I really need a hint.
 
Last edited:
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I don't think you need anything fancy here: just notice that |x|<=2.
 
You are right :) i made it. Tnx
 

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