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?
calculus integration
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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?
calculus integration
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add a comment |
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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?
calculus integration
$endgroup$
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
calculus integration
asked Jan 8 at 16:34
Emma PascoeEmma Pascoe
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2 Answers
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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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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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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.
$endgroup$
add a comment |
$begingroup$
$min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.
$endgroup$
add a comment |
$begingroup$
$min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.
$endgroup$
$min(a, b)=dfrac{a+b-|a-b|}{2}$. If $a$ is an integrable function and $b$ is a constant, then the right hand side should be Lebesgue integrable.
answered Jan 8 at 16:41
EuxhenHEuxhenH
482210
482210
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I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?
$endgroup$
add a comment |
$begingroup$
I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?
$endgroup$
add a comment |
$begingroup$
I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?
$endgroup$
I'm not very sure about my reasoning, but wouldn't $f(x):=displaystyle frac{1}{x}$ on [-1,1] make a counter-example?
answered Jan 8 at 16:46
Edward H.Edward H.
1739
1739
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