min(f(x), 5) integrability












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Q: If $f(x)$ is integrable on $[a,b]$, let $g(x)=min(f(x),5)$. Is $g(x)$ integrable on $[a,b]$?



Does the number that g(x) chooses matter? (ie. can the 5 really just be any constant?)



My Start: I would think yes, just because any part where g(x) chooses f(x) is obviously integrable, and any constant is also integrable so is it just integrable everywhere?










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$endgroup$

















    1












    $begingroup$


    Q: If $f(x)$ is integrable on $[a,b]$, let $g(x)=min(f(x),5)$. Is $g(x)$ integrable on $[a,b]$?



    Does the number that g(x) chooses matter? (ie. can the 5 really just be any constant?)



    My Start: I would think yes, just because any part where g(x) chooses f(x) is obviously integrable, and any constant is also integrable so is it just integrable everywhere?










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      Q: If $f(x)$ is integrable on $[a,b]$, let $g(x)=min(f(x),5)$. Is $g(x)$ integrable on $[a,b]$?



      Does the number that g(x) chooses matter? (ie. can the 5 really just be any constant?)



      My Start: I would think yes, just because any part where g(x) chooses f(x) is obviously integrable, and any constant is also integrable so is it just integrable everywhere?










      share|cite|improve this question









      $endgroup$




      Q: If $f(x)$ is integrable on $[a,b]$, let $g(x)=min(f(x),5)$. Is $g(x)$ integrable on $[a,b]$?



      Does the number that g(x) chooses matter? (ie. can the 5 really just be any constant?)



      My Start: I would think yes, just because any part where g(x) chooses f(x) is obviously integrable, and any constant is also integrable so is it just integrable everywhere?







      calculus integration






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      asked Jan 8 at 16:34









      Emma PascoeEmma Pascoe

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          $min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.






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            0












            $begingroup$

            I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?






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              2 Answers
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              $begingroup$

              $min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.






              share|cite|improve this answer









              $endgroup$


















                1












                $begingroup$

                $min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.






                share|cite|improve this answer









                $endgroup$
















                  1












                  1








                  1





                  $begingroup$

                  $min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.






                  share|cite|improve this answer









                  $endgroup$



                  $min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered Jan 8 at 16:41









                  EuxhenHEuxhenH

                  482210




                  482210























                      0












                      $begingroup$

                      I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?






                      share|cite|improve this answer









                      $endgroup$


















                        0












                        $begingroup$

                        I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?






                        share|cite|improve this answer









                        $endgroup$
















                          0












                          0








                          0





                          $begingroup$

                          I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?






                          share|cite|improve this answer









                          $endgroup$



                          I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered Jan 8 at 16:46









                          Edward H.Edward H.

                          1739




                          1739






























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