Using the $varepsilon − N$ definition of the limit, prove that $lim limits_ntoinfty frac(n^2 + 1) (n^2 + 2) = 1$.Use the $varepsilon$-$delta$ definition of a limit to prove this.Prove limit doesn't exist using $delta$-$varepsilon$Can we prove that there is no limit at $x=0$ for $f(x)=1/x$ using epsilon-delta definition?Directly prove using the definition of convergence $limlimits_n to inftyfracn^2 +1 4n -1 = infty$How to prove $limlimits_nto infty(a_n+2b_n)=L+2M$ using the formal definition of limit of sequence?How to write $varepsilon$–$delta$ definition of $limlimits_ntoinftyf(a_n)=f(c)$?Proving the limit of $frac1n^2+n$ = 0 using the $epsilon$ - N definitionFormal limit definition in $limlimits_xto+infty fracx^2+29x=+infty$What exactly does the $varepsilon$-$delta$ definition of limits prove?Prove that the sequence converges to using the $varepsilon$-$N$ definition of a limit
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Using the $varepsilon − N$ definition of the limit, prove that $lim limits_ntoinfty frac(n^2 + 1) (n^2 + 2) = 1$.
Use the $varepsilon$-$delta$ definition of a limit to prove this.Prove limit doesn't exist using $delta$-$varepsilon$Can we prove that there is no limit at $x=0$ for $f(x)=1/x$ using epsilon-delta definition?Directly prove using the definition of convergence $limlimits_n to inftyfracn^2 +1 4n -1 = infty$How to prove $limlimits_nto infty(a_n+2b_n)=L+2M$ using the formal definition of limit of sequence?How to write $varepsilon$–$delta$ definition of $limlimits_ntoinftyf(a_n)=f(c)$?Proving the limit of $frac1n^2+n$ = 0 using the $epsilon$ - N definitionFormal limit definition in $limlimits_xto+infty fracx^2+29x=+infty$What exactly does the $varepsilon$-$delta$ definition of limits prove?Prove that the sequence converges to using the $varepsilon$-$N$ definition of a limit
$begingroup$
Using the $ε − N$ definition of the limit, prove that
$displaystylelim limits_ntoinfty frac(n^2 + 1) (n^2 + 2) = 1$.
In other words, given $varepsilon> 0$, find explicitly a natural number $N$ which
satisfies the statement in the definition of the limit.
limits epsilon-delta
New contributor
$endgroup$
add a comment |
$begingroup$
Using the $ε − N$ definition of the limit, prove that
$displaystylelim limits_ntoinfty frac(n^2 + 1) (n^2 + 2) = 1$.
In other words, given $varepsilon> 0$, find explicitly a natural number $N$ which
satisfies the statement in the definition of the limit.
limits epsilon-delta
New contributor
$endgroup$
1
$begingroup$
What have you tried?
$endgroup$
– Kezer
Mar 13 at 10:48
$begingroup$
trying to divide top and bottom by n^2 but dont know what to do now
$endgroup$
– john smith
Mar 13 at 10:51
1
$begingroup$
Perhaps start by writing out the definition.
$endgroup$
– Kezer
Mar 13 at 10:53
$begingroup$
is that the epsilon >0 thing, then I say n> N?
$endgroup$
– john smith
Mar 13 at 10:55
$begingroup$
Yes, that's it.
$endgroup$
– frabala
Mar 13 at 11:10
add a comment |
$begingroup$
Using the $ε − N$ definition of the limit, prove that
$displaystylelim limits_ntoinfty frac(n^2 + 1) (n^2 + 2) = 1$.
In other words, given $varepsilon> 0$, find explicitly a natural number $N$ which
satisfies the statement in the definition of the limit.
limits epsilon-delta
New contributor
$endgroup$
Using the $ε − N$ definition of the limit, prove that
$displaystylelim limits_ntoinfty frac(n^2 + 1) (n^2 + 2) = 1$.
In other words, given $varepsilon> 0$, find explicitly a natural number $N$ which
satisfies the statement in the definition of the limit.
limits epsilon-delta
limits epsilon-delta
New contributor
New contributor
edited Mar 13 at 10:57
Yadati Kiran
2,1061621
2,1061621
New contributor
asked Mar 13 at 10:40
john smithjohn smith
64
64
New contributor
New contributor
1
$begingroup$
What have you tried?
$endgroup$
– Kezer
Mar 13 at 10:48
$begingroup$
trying to divide top and bottom by n^2 but dont know what to do now
$endgroup$
– john smith
Mar 13 at 10:51
1
$begingroup$
Perhaps start by writing out the definition.
$endgroup$
– Kezer
Mar 13 at 10:53
$begingroup$
is that the epsilon >0 thing, then I say n> N?
$endgroup$
– john smith
Mar 13 at 10:55
$begingroup$
Yes, that's it.
$endgroup$
– frabala
Mar 13 at 11:10
add a comment |
1
$begingroup$
What have you tried?
$endgroup$
– Kezer
Mar 13 at 10:48
$begingroup$
trying to divide top and bottom by n^2 but dont know what to do now
$endgroup$
– john smith
Mar 13 at 10:51
1
$begingroup$
Perhaps start by writing out the definition.
$endgroup$
– Kezer
Mar 13 at 10:53
$begingroup$
is that the epsilon >0 thing, then I say n> N?
$endgroup$
– john smith
Mar 13 at 10:55
$begingroup$
Yes, that's it.
$endgroup$
– frabala
Mar 13 at 11:10
1
1
$begingroup$
What have you tried?
$endgroup$
– Kezer
Mar 13 at 10:48
$begingroup$
What have you tried?
$endgroup$
– Kezer
Mar 13 at 10:48
$begingroup$
trying to divide top and bottom by n^2 but dont know what to do now
$endgroup$
– john smith
Mar 13 at 10:51
$begingroup$
trying to divide top and bottom by n^2 but dont know what to do now
$endgroup$
– john smith
Mar 13 at 10:51
1
1
$begingroup$
Perhaps start by writing out the definition.
$endgroup$
– Kezer
Mar 13 at 10:53
$begingroup$
Perhaps start by writing out the definition.
$endgroup$
– Kezer
Mar 13 at 10:53
$begingroup$
is that the epsilon >0 thing, then I say n> N?
$endgroup$
– john smith
Mar 13 at 10:55
$begingroup$
is that the epsilon >0 thing, then I say n> N?
$endgroup$
– john smith
Mar 13 at 10:55
$begingroup$
Yes, that's it.
$endgroup$
– frabala
Mar 13 at 11:10
$begingroup$
Yes, that's it.
$endgroup$
– frabala
Mar 13 at 11:10
add a comment |
3 Answers
3
active
oldest
votes
$begingroup$
Let $varepsilon > 0$.
Define $$N = lfloor sqrtfrac1varepsilon-2rfloor +1$$
For all $n geq N$, you have then $$n geq sqrtfrac1varepsilon-2$$
so
$$n^2+2 geq frac1varepsilon$$
so $$frac1n^2+2 leq varepsilon$$
so
$$left| fracn^2+1n^2+2 - 1 right| leq varepsilon$$
By the definition of the limit, this shows that
$$fracn^2+1n^2+2 rightarrow 1 $$
$endgroup$
add a comment |
$begingroup$
$$|a_n-1|=1over n^2+2$$therefore if $n>1over sqrtepsilon$ we obtain $$n^2+2>1over epsilon+2>1over epsilon$$and $$|a_n-1|<epsilon$$ hence the result.
$endgroup$
add a comment |
$begingroup$
First of all rewrite the expression:
$a_n := fracn^2+1n^2+2 = 1-frac1n^2+2$.
Choose $N in mathbbN$ and let $n geq N$. Then we have:
$ Big | a_n -1 Big | = frac1n^2+2 leq frac1n^2 leq frac1N^2$
Do you have an idea how to choose $N in mathbbN$ from this inequality?
New contributor
$endgroup$
add a comment |
Your Answer
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3 Answers
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3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Let $varepsilon > 0$.
Define $$N = lfloor sqrtfrac1varepsilon-2rfloor +1$$
For all $n geq N$, you have then $$n geq sqrtfrac1varepsilon-2$$
so
$$n^2+2 geq frac1varepsilon$$
so $$frac1n^2+2 leq varepsilon$$
so
$$left| fracn^2+1n^2+2 - 1 right| leq varepsilon$$
By the definition of the limit, this shows that
$$fracn^2+1n^2+2 rightarrow 1 $$
$endgroup$
add a comment |
$begingroup$
Let $varepsilon > 0$.
Define $$N = lfloor sqrtfrac1varepsilon-2rfloor +1$$
For all $n geq N$, you have then $$n geq sqrtfrac1varepsilon-2$$
so
$$n^2+2 geq frac1varepsilon$$
so $$frac1n^2+2 leq varepsilon$$
so
$$left| fracn^2+1n^2+2 - 1 right| leq varepsilon$$
By the definition of the limit, this shows that
$$fracn^2+1n^2+2 rightarrow 1 $$
$endgroup$
add a comment |
$begingroup$
Let $varepsilon > 0$.
Define $$N = lfloor sqrtfrac1varepsilon-2rfloor +1$$
For all $n geq N$, you have then $$n geq sqrtfrac1varepsilon-2$$
so
$$n^2+2 geq frac1varepsilon$$
so $$frac1n^2+2 leq varepsilon$$
so
$$left| fracn^2+1n^2+2 - 1 right| leq varepsilon$$
By the definition of the limit, this shows that
$$fracn^2+1n^2+2 rightarrow 1 $$
$endgroup$
Let $varepsilon > 0$.
Define $$N = lfloor sqrtfrac1varepsilon-2rfloor +1$$
For all $n geq N$, you have then $$n geq sqrtfrac1varepsilon-2$$
so
$$n^2+2 geq frac1varepsilon$$
so $$frac1n^2+2 leq varepsilon$$
so
$$left| fracn^2+1n^2+2 - 1 right| leq varepsilon$$
By the definition of the limit, this shows that
$$fracn^2+1n^2+2 rightarrow 1 $$
answered Mar 13 at 11:48
TheSilverDoeTheSilverDoe
4,085114
4,085114
add a comment |
add a comment |
$begingroup$
$$|a_n-1|=1over n^2+2$$therefore if $n>1over sqrtepsilon$ we obtain $$n^2+2>1over epsilon+2>1over epsilon$$and $$|a_n-1|<epsilon$$ hence the result.
$endgroup$
add a comment |
$begingroup$
$$|a_n-1|=1over n^2+2$$therefore if $n>1over sqrtepsilon$ we obtain $$n^2+2>1over epsilon+2>1over epsilon$$and $$|a_n-1|<epsilon$$ hence the result.
$endgroup$
add a comment |
$begingroup$
$$|a_n-1|=1over n^2+2$$therefore if $n>1over sqrtepsilon$ we obtain $$n^2+2>1over epsilon+2>1over epsilon$$and $$|a_n-1|<epsilon$$ hence the result.
$endgroup$
$$|a_n-1|=1over n^2+2$$therefore if $n>1over sqrtepsilon$ we obtain $$n^2+2>1over epsilon+2>1over epsilon$$and $$|a_n-1|<epsilon$$ hence the result.
answered Mar 13 at 12:39
Mostafa AyazMostafa Ayaz
16.5k3939
16.5k3939
add a comment |
add a comment |
$begingroup$
First of all rewrite the expression:
$a_n := fracn^2+1n^2+2 = 1-frac1n^2+2$.
Choose $N in mathbbN$ and let $n geq N$. Then we have:
$ Big | a_n -1 Big | = frac1n^2+2 leq frac1n^2 leq frac1N^2$
Do you have an idea how to choose $N in mathbbN$ from this inequality?
New contributor
$endgroup$
add a comment |
$begingroup$
First of all rewrite the expression:
$a_n := fracn^2+1n^2+2 = 1-frac1n^2+2$.
Choose $N in mathbbN$ and let $n geq N$. Then we have:
$ Big | a_n -1 Big | = frac1n^2+2 leq frac1n^2 leq frac1N^2$
Do you have an idea how to choose $N in mathbbN$ from this inequality?
New contributor
$endgroup$
add a comment |
$begingroup$
First of all rewrite the expression:
$a_n := fracn^2+1n^2+2 = 1-frac1n^2+2$.
Choose $N in mathbbN$ and let $n geq N$. Then we have:
$ Big | a_n -1 Big | = frac1n^2+2 leq frac1n^2 leq frac1N^2$
Do you have an idea how to choose $N in mathbbN$ from this inequality?
New contributor
$endgroup$
First of all rewrite the expression:
$a_n := fracn^2+1n^2+2 = 1-frac1n^2+2$.
Choose $N in mathbbN$ and let $n geq N$. Then we have:
$ Big | a_n -1 Big | = frac1n^2+2 leq frac1n^2 leq frac1N^2$
Do you have an idea how to choose $N in mathbbN$ from this inequality?
New contributor
edited Mar 13 at 12:51
New contributor
answered Mar 13 at 12:24
GordonFreemanGordonFreeman
63
63
New contributor
New contributor
add a comment |
add a comment |
john smith is a new contributor. Be nice, and check out our Code of Conduct.
john smith is a new contributor. Be nice, and check out our Code of Conduct.
john smith is a new contributor. Be nice, and check out our Code of Conduct.
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1
$begingroup$
What have you tried?
$endgroup$
– Kezer
Mar 13 at 10:48
$begingroup$
trying to divide top and bottom by n^2 but dont know what to do now
$endgroup$
– john smith
Mar 13 at 10:51
1
$begingroup$
Perhaps start by writing out the definition.
$endgroup$
– Kezer
Mar 13 at 10:53
$begingroup$
is that the epsilon >0 thing, then I say n> N?
$endgroup$
– john smith
Mar 13 at 10:55
$begingroup$
Yes, that's it.
$endgroup$
– frabala
Mar 13 at 11:10