Ways of checking pointwise convergence











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According to the definition of pointwise convergence:
A sequence $f_m(x)$ of real valued functions defined on D a subset of real numbers
is said to be pointwise convergent to$f(d)$ at a point $depsilon D$ if for all $epsilon$>0 there exists a $m_0$ such that $|f_m(d)-f(d)|$<$epsilon$ for all $m>m_0$



to check pointwise convergence a given interval for a given function , do we need to do all this work above? or we can simply find the $lim mto$infinity for the function $f_m(x)$ and if it exists then say that the function is pointwise convergent?










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    It's the same thing. If you find $lim_{m to infty} f_m(d) = f(d)$ for all $d$ and write down the formal definition of limit, you'll just get what's in your first paragraph.
    – angryavian
    Nov 24 at 0:21










  • Thanks a lot for the help:)
    – Cosmic
    Nov 24 at 0:22















up vote
0
down vote

favorite
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According to the definition of pointwise convergence:
A sequence $f_m(x)$ of real valued functions defined on D a subset of real numbers
is said to be pointwise convergent to$f(d)$ at a point $depsilon D$ if for all $epsilon$>0 there exists a $m_0$ such that $|f_m(d)-f(d)|$<$epsilon$ for all $m>m_0$



to check pointwise convergence a given interval for a given function , do we need to do all this work above? or we can simply find the $lim mto$infinity for the function $f_m(x)$ and if it exists then say that the function is pointwise convergent?










share|cite|improve this question


















  • 1




    It's the same thing. If you find $lim_{m to infty} f_m(d) = f(d)$ for all $d$ and write down the formal definition of limit, you'll just get what's in your first paragraph.
    – angryavian
    Nov 24 at 0:21










  • Thanks a lot for the help:)
    – Cosmic
    Nov 24 at 0:22













up vote
0
down vote

favorite
1









up vote
0
down vote

favorite
1






1





According to the definition of pointwise convergence:
A sequence $f_m(x)$ of real valued functions defined on D a subset of real numbers
is said to be pointwise convergent to$f(d)$ at a point $depsilon D$ if for all $epsilon$>0 there exists a $m_0$ such that $|f_m(d)-f(d)|$<$epsilon$ for all $m>m_0$



to check pointwise convergence a given interval for a given function , do we need to do all this work above? or we can simply find the $lim mto$infinity for the function $f_m(x)$ and if it exists then say that the function is pointwise convergent?










share|cite|improve this question













According to the definition of pointwise convergence:
A sequence $f_m(x)$ of real valued functions defined on D a subset of real numbers
is said to be pointwise convergent to$f(d)$ at a point $depsilon D$ if for all $epsilon$>0 there exists a $m_0$ such that $|f_m(d)-f(d)|$<$epsilon$ for all $m>m_0$



to check pointwise convergence a given interval for a given function , do we need to do all this work above? or we can simply find the $lim mto$infinity for the function $f_m(x)$ and if it exists then say that the function is pointwise convergent?







real-analysis pointwise-convergence sequence-of-function






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share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Nov 23 at 23:15









Cosmic

569




569








  • 1




    It's the same thing. If you find $lim_{m to infty} f_m(d) = f(d)$ for all $d$ and write down the formal definition of limit, you'll just get what's in your first paragraph.
    – angryavian
    Nov 24 at 0:21










  • Thanks a lot for the help:)
    – Cosmic
    Nov 24 at 0:22














  • 1




    It's the same thing. If you find $lim_{m to infty} f_m(d) = f(d)$ for all $d$ and write down the formal definition of limit, you'll just get what's in your first paragraph.
    – angryavian
    Nov 24 at 0:21










  • Thanks a lot for the help:)
    – Cosmic
    Nov 24 at 0:22








1




1




It's the same thing. If you find $lim_{m to infty} f_m(d) = f(d)$ for all $d$ and write down the formal definition of limit, you'll just get what's in your first paragraph.
– angryavian
Nov 24 at 0:21




It's the same thing. If you find $lim_{m to infty} f_m(d) = f(d)$ for all $d$ and write down the formal definition of limit, you'll just get what's in your first paragraph.
– angryavian
Nov 24 at 0:21












Thanks a lot for the help:)
– Cosmic
Nov 24 at 0:22




Thanks a lot for the help:)
– Cosmic
Nov 24 at 0:22















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