Let $f:Xto [0,1]$ be the function defined by $f(x_i)_{ige 1}=sum _{ige 1}x_i2^{-i}$. Choose the correct...
$begingroup$
Let $X={(x_i)_{ige 1}:x_iin {0,1}$ for all $ige 1}$ with the metric $d((x_i),(y_i))=sum_{ige 1}|x_i-y_i|2^{-i}.$ Let $f:Xto [0,1]$ be the function defined by $f(x_i)_{ige 1}=sum _{ige 1}x_i2^{-i}$.
Choose the correct statements from below :
$1)$$f$ is continuous
$2)$$f$ is onto
$3)$$f$ is one-one
$4)$$f$ is open
My attempt : option $1)$ is true by triangle inequality.
$2)$ is true as it is a binary representation
im confused about option 3, 4
any hints/solution
thanks u
general-topology
$endgroup$
closed as off-topic by RRL, amWhy, Paul Frost, clathratus, Leucippus Jan 13 at 7:27
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – RRL, amWhy, Paul Frost, clathratus, Leucippus
If this question can be reworded to fit the rules in the help center, please edit the question.
add a comment |
$begingroup$
Let $X={(x_i)_{ige 1}:x_iin {0,1}$ for all $ige 1}$ with the metric $d((x_i),(y_i))=sum_{ige 1}|x_i-y_i|2^{-i}.$ Let $f:Xto [0,1]$ be the function defined by $f(x_i)_{ige 1}=sum _{ige 1}x_i2^{-i}$.
Choose the correct statements from below :
$1)$$f$ is continuous
$2)$$f$ is onto
$3)$$f$ is one-one
$4)$$f$ is open
My attempt : option $1)$ is true by triangle inequality.
$2)$ is true as it is a binary representation
im confused about option 3, 4
any hints/solution
thanks u
general-topology
$endgroup$
closed as off-topic by RRL, amWhy, Paul Frost, clathratus, Leucippus Jan 13 at 7:27
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – RRL, amWhy, Paul Frost, clathratus, Leucippus
If this question can be reworded to fit the rules in the help center, please edit the question.
add a comment |
$begingroup$
Let $X={(x_i)_{ige 1}:x_iin {0,1}$ for all $ige 1}$ with the metric $d((x_i),(y_i))=sum_{ige 1}|x_i-y_i|2^{-i}.$ Let $f:Xto [0,1]$ be the function defined by $f(x_i)_{ige 1}=sum _{ige 1}x_i2^{-i}$.
Choose the correct statements from below :
$1)$$f$ is continuous
$2)$$f$ is onto
$3)$$f$ is one-one
$4)$$f$ is open
My attempt : option $1)$ is true by triangle inequality.
$2)$ is true as it is a binary representation
im confused about option 3, 4
any hints/solution
thanks u
general-topology
$endgroup$
Let $X={(x_i)_{ige 1}:x_iin {0,1}$ for all $ige 1}$ with the metric $d((x_i),(y_i))=sum_{ige 1}|x_i-y_i|2^{-i}.$ Let $f:Xto [0,1]$ be the function defined by $f(x_i)_{ige 1}=sum _{ige 1}x_i2^{-i}$.
Choose the correct statements from below :
$1)$$f$ is continuous
$2)$$f$ is onto
$3)$$f$ is one-one
$4)$$f$ is open
My attempt : option $1)$ is true by triangle inequality.
$2)$ is true as it is a binary representation
im confused about option 3, 4
any hints/solution
thanks u
general-topology
general-topology
asked Dec 20 '18 at 8:38
jasminejasmine
1,766417
1,766417
closed as off-topic by RRL, amWhy, Paul Frost, clathratus, Leucippus Jan 13 at 7:27
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – RRL, amWhy, Paul Frost, clathratus, Leucippus
If this question can be reworded to fit the rules in the help center, please edit the question.
closed as off-topic by RRL, amWhy, Paul Frost, clathratus, Leucippus Jan 13 at 7:27
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – RRL, amWhy, Paul Frost, clathratus, Leucippus
If this question can be reworded to fit the rules in the help center, please edit the question.
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
$f(1,0,0,cdots)=f(0,1,1,cdots)$ so $f$ is not one-to one.
${(x_i):x_1=0}equiv {(x_i):x_1 neq 1}$ is open and its image is $[0,frac 1 2]$ which is not open. Hence $f$ is not an open map.
$endgroup$
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
$f(1,0,0,cdots)=f(0,1,1,cdots)$ so $f$ is not one-to one.
${(x_i):x_1=0}equiv {(x_i):x_1 neq 1}$ is open and its image is $[0,frac 1 2]$ which is not open. Hence $f$ is not an open map.
$endgroup$
add a comment |
$begingroup$
$f(1,0,0,cdots)=f(0,1,1,cdots)$ so $f$ is not one-to one.
${(x_i):x_1=0}equiv {(x_i):x_1 neq 1}$ is open and its image is $[0,frac 1 2]$ which is not open. Hence $f$ is not an open map.
$endgroup$
add a comment |
$begingroup$
$f(1,0,0,cdots)=f(0,1,1,cdots)$ so $f$ is not one-to one.
${(x_i):x_1=0}equiv {(x_i):x_1 neq 1}$ is open and its image is $[0,frac 1 2]$ which is not open. Hence $f$ is not an open map.
$endgroup$
$f(1,0,0,cdots)=f(0,1,1,cdots)$ so $f$ is not one-to one.
${(x_i):x_1=0}equiv {(x_i):x_1 neq 1}$ is open and its image is $[0,frac 1 2]$ which is not open. Hence $f$ is not an open map.
answered Dec 20 '18 at 8:57
Kavi Rama MurthyKavi Rama Murthy
60.5k42161
60.5k42161
add a comment |
add a comment |