Is there a fixed point theorem I could use to solve this problem?












3














let $E = C([0,1]),,,$ $K : E to E, ,,
(Kf)(x) = int_0^1K(x,y)f(y)dy$



also $|K| leq a < 1$



I want to prove that there for $g in E$ there exists a unique $f_g in E$ that satisfies the following equation :



$f_g + Kf_g = g$



which is equivalent to showing that $T : E to E,,,T(f) = g-Kf$ has a fixed point.



with what I have in hands I feel like there must be some theorem I'm missing.



any help will be greatly appreciated !










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  • You have not specified what kind of function $K(x,y)$ is what $|K|$ stands for.
    – Kavi Rama Murthy
    11 mins ago
















3














let $E = C([0,1]),,,$ $K : E to E, ,,
(Kf)(x) = int_0^1K(x,y)f(y)dy$



also $|K| leq a < 1$



I want to prove that there for $g in E$ there exists a unique $f_g in E$ that satisfies the following equation :



$f_g + Kf_g = g$



which is equivalent to showing that $T : E to E,,,T(f) = g-Kf$ has a fixed point.



with what I have in hands I feel like there must be some theorem I'm missing.



any help will be greatly appreciated !










share|cite|improve this question






















  • You have not specified what kind of function $K(x,y)$ is what $|K|$ stands for.
    – Kavi Rama Murthy
    11 mins ago














3












3








3


0





let $E = C([0,1]),,,$ $K : E to E, ,,
(Kf)(x) = int_0^1K(x,y)f(y)dy$



also $|K| leq a < 1$



I want to prove that there for $g in E$ there exists a unique $f_g in E$ that satisfies the following equation :



$f_g + Kf_g = g$



which is equivalent to showing that $T : E to E,,,T(f) = g-Kf$ has a fixed point.



with what I have in hands I feel like there must be some theorem I'm missing.



any help will be greatly appreciated !










share|cite|improve this question













let $E = C([0,1]),,,$ $K : E to E, ,,
(Kf)(x) = int_0^1K(x,y)f(y)dy$



also $|K| leq a < 1$



I want to prove that there for $g in E$ there exists a unique $f_g in E$ that satisfies the following equation :



$f_g + Kf_g = g$



which is equivalent to showing that $T : E to E,,,T(f) = g-Kf$ has a fixed point.



with what I have in hands I feel like there must be some theorem I'm missing.



any help will be greatly appreciated !







functional-analysis fixed-point-theorems






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asked 1 hour ago









rapidracim

1,3961319




1,3961319












  • You have not specified what kind of function $K(x,y)$ is what $|K|$ stands for.
    – Kavi Rama Murthy
    11 mins ago


















  • You have not specified what kind of function $K(x,y)$ is what $|K|$ stands for.
    – Kavi Rama Murthy
    11 mins ago
















You have not specified what kind of function $K(x,y)$ is what $|K|$ stands for.
– Kavi Rama Murthy
11 mins ago




You have not specified what kind of function $K(x,y)$ is what $|K|$ stands for.
– Kavi Rama Murthy
11 mins ago










1 Answer
1






active

oldest

votes


















3














You can apply the Contraction mapping, a.k.a. Banach's Fixed Point Theorem. Given $f,hin C([0,1])$,
$$
|Tf-Th|leint_0^1|K(x,y)|,|f(y)-h(y)|,dyle|K|,|f-h|<a,|f-h|,
$$

with $0<a<1$.






share|cite|improve this answer





















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    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    3














    You can apply the Contraction mapping, a.k.a. Banach's Fixed Point Theorem. Given $f,hin C([0,1])$,
    $$
    |Tf-Th|leint_0^1|K(x,y)|,|f(y)-h(y)|,dyle|K|,|f-h|<a,|f-h|,
    $$

    with $0<a<1$.






    share|cite|improve this answer


























      3














      You can apply the Contraction mapping, a.k.a. Banach's Fixed Point Theorem. Given $f,hin C([0,1])$,
      $$
      |Tf-Th|leint_0^1|K(x,y)|,|f(y)-h(y)|,dyle|K|,|f-h|<a,|f-h|,
      $$

      with $0<a<1$.






      share|cite|improve this answer
























        3












        3








        3






        You can apply the Contraction mapping, a.k.a. Banach's Fixed Point Theorem. Given $f,hin C([0,1])$,
        $$
        |Tf-Th|leint_0^1|K(x,y)|,|f(y)-h(y)|,dyle|K|,|f-h|<a,|f-h|,
        $$

        with $0<a<1$.






        share|cite|improve this answer












        You can apply the Contraction mapping, a.k.a. Banach's Fixed Point Theorem. Given $f,hin C([0,1])$,
        $$
        |Tf-Th|leint_0^1|K(x,y)|,|f(y)-h(y)|,dyle|K|,|f-h|<a,|f-h|,
        $$

        with $0<a<1$.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered 59 mins ago









        Julián Aguirre

        67.4k24094




        67.4k24094






























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