Theorem List for Intuitionistic Logic Explorer - 15201-15300 *Has distinct variable
group(s)
| Type | Label | Description |
| Statement |
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| Theorem | mstri2 15201 |
Triangle inequality for the distance function of a metric space.
(Contributed by Mario Carneiro, 2-Oct-2015.)
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| Theorem | xmstri 15202 |
Triangle inequality for the distance function of a metric space.
Definition 14-1.1(d) of [Gleason] p.
223. (Contributed by Mario
Carneiro, 2-Oct-2015.)
|
           
 
                   |
| |
| Theorem | mstri 15203 |
Triangle inequality for the distance function of a metric space.
Definition 14-1.1(d) of [Gleason] p.
223. (Contributed by Mario
Carneiro, 2-Oct-2015.)
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| Theorem | xmstri3 15204 |
Triangle inequality for the distance function of an extended metric.
(Contributed by Mario Carneiro, 2-Oct-2015.)
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| Theorem | mstri3 15205 |
Triangle inequality for the distance function of a metric space.
(Contributed by Mario Carneiro, 2-Oct-2015.)
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| Theorem | msrtri 15206 |
Reverse triangle inequality for the distance function of a metric space.
(Contributed by Mario Carneiro, 4-Oct-2015.)
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| Theorem | xmspropd 15207 |
Property deduction for an extended metric space. (Contributed by Mario
Carneiro, 4-Oct-2015.)
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| Theorem | mspropd 15208 |
Property deduction for a metric space. (Contributed by Mario Carneiro,
4-Oct-2015.)
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| |
| Theorem | setsmsbasg 15209 |
The base set of a constructed metric space. (Contributed by Mario
Carneiro, 28-Aug-2015.)
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sSet  TopSet  
       
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| |
| Theorem | setsmsdsg 15210 |
The distance function of a constructed metric space. (Contributed by
Mario Carneiro, 28-Aug-2015.)
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sSet  TopSet  
       
                  |
| |
| Theorem | setsmstsetg 15211 |
The topology of a constructed metric space. (Contributed by Mario
Carneiro, 28-Aug-2015.) (Revised by Jim Kingdon, 7-May-2023.)
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sSet  TopSet  
       
            TopSet    |
| |
| Theorem | mopni 15212* |
An open set of a metric space includes a ball around each of its points.
(Contributed by NM, 3-Sep-2006.) (Revised by Mario Carneiro,
12-Nov-2013.)
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| Theorem | mopni2 15213* |
An open set of a metric space includes a ball around each of its points.
(Contributed by NM, 2-May-2007.) (Revised by Mario Carneiro,
12-Nov-2013.)
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                       |
| |
| Theorem | mopni3 15214* |
An open set of a metric space includes an arbitrarily small ball around
each of its points. (Contributed by NM, 20-Sep-2007.) (Revised by
Mario Carneiro, 12-Nov-2013.)
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| Theorem | blssopn 15215 |
The balls of a metric space are open sets. (Contributed by NM,
12-Sep-2006.) (Revised by Mario Carneiro, 23-Dec-2013.)
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| Theorem | unimopn 15216 |
The union of a collection of open sets of a metric space is open.
Theorem T2 of [Kreyszig] p. 19.
(Contributed by NM, 4-Sep-2006.)
(Revised by Mario Carneiro, 23-Dec-2013.)
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| Theorem | mopnin 15217 |
The intersection of two open sets of a metric space is open.
(Contributed by NM, 4-Sep-2006.) (Revised by Mario Carneiro,
23-Dec-2013.)
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| |
| Theorem | mopn0 15218 |
The empty set is an open set of a metric space. Part of Theorem T1 of
[Kreyszig] p. 19. (Contributed by NM,
4-Sep-2006.)
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| Theorem | rnblopn 15219 |
A ball of a metric space is an open set. (Contributed by NM,
12-Sep-2006.)
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| Theorem | blopn 15220 |
A ball of a metric space is an open set. (Contributed by NM,
9-Mar-2007.) (Revised by Mario Carneiro, 12-Nov-2013.)
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| Theorem | neibl 15221* |
The neighborhoods around a point of a metric space are those
subsets containing a ball around . Definition of neighborhood in
[Kreyszig] p. 19. (Contributed by NM,
8-Nov-2007.) (Revised by Mario
Carneiro, 23-Dec-2013.)
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                                     |
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| Theorem | blnei 15222 |
A ball around a point is a neighborhood of the point. (Contributed by
NM, 8-Nov-2007.) (Revised by Mario Carneiro, 24-Aug-2015.)
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| Theorem | blsscls2 15223* |
A smaller closed ball is contained in a larger open ball. (Contributed
by Mario Carneiro, 10-Jan-2014.)
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| Theorem | metss 15224* |
Two ways of saying that metric generates a finer topology than
metric .
(Contributed by Mario Carneiro, 12-Nov-2013.) (Revised
by Mario Carneiro, 24-Aug-2015.)
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| Theorem | metequiv 15225* |
Two ways of saying that two metrics generate the same topology. Two
metrics satisfying the right-hand side are said to be (topologically)
equivalent. (Contributed by Jeff Hankins, 21-Jun-2009.) (Revised by
Mario Carneiro, 12-Nov-2013.)
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| Theorem | metequiv2 15226* |
If there is a sequence of radii approaching zero for which the balls of
both metrics coincide, then the generated topologies are equivalent.
(Contributed by Mario Carneiro, 26-Aug-2015.)
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| Theorem | metss2lem 15227* |
Lemma for metss2 15228. (Contributed by Mario Carneiro,
14-Sep-2015.)
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| Theorem | metss2 15228* |
If the metric is
"strongly finer" than (meaning that there
is a positive real constant such that
   
    ), then generates a finer
topology. (Using this theorem twice in each direction states that if
two metrics are strongly equivalent, then they generate the same
topology.) (Contributed by Mario Carneiro, 14-Sep-2015.)
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| Theorem | comet 15229* |
The composition of an extended metric with a monotonic subadditive
function is an extended metric. (Contributed by Mario Carneiro,
21-Mar-2015.)
|
                          
    
        
           
   
             
              
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| Theorem | bdmetval 15230* |
Value of the standard bounded metric. (Contributed by Mario Carneiro,
26-Aug-2015.) (Revised by Jim Kingdon, 9-May-2023.)
|
  inf                     
 
    inf        
   |
| |
| Theorem | bdxmet 15231* |
The standard bounded metric is an extended metric given an extended
metric and a positive extended real cutoff. (Contributed by Mario
Carneiro, 26-Aug-2015.) (Revised by Jim Kingdon, 9-May-2023.)
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  inf                 

       |
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| Theorem | bdmet 15232* |
The standard bounded metric is a proper metric given an extended metric
and a positive real cutoff. (Contributed by Mario Carneiro,
26-Aug-2015.) (Revised by Jim Kingdon, 19-May-2023.)
|
  inf                         |
| |
| Theorem | bdbl 15233* |
The standard bounded metric corresponding to generates the same
balls as for
radii less than .
(Contributed by Mario
Carneiro, 26-Aug-2015.) (Revised by Jim Kingdon, 19-May-2023.)
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  inf                  
 
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| Theorem | bdmopn 15234* |
The standard bounded metric corresponding to generates the same
topology as .
(Contributed by Mario Carneiro, 26-Aug-2015.)
(Revised by Jim Kingdon, 19-May-2023.)
|
  inf                             |
| |
| Theorem | mopnex 15235* |
The topology generated by an extended metric can also be generated by a
true metric. Thus, "metrizable topologies" can equivalently
be defined
in terms of metrics or extended metrics. (Contributed by Mario
Carneiro, 26-Aug-2015.)
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| |
| Theorem | metrest 15236 |
Two alternate formulations of a subspace topology of a metric space
topology. (Contributed by Jeff Hankins, 19-Aug-2009.) (Proof shortened
by Mario Carneiro, 5-Jan-2014.)
|
                  
 
↾t    |
| |
| Theorem | xmetxp 15237* |
The maximum metric (Chebyshev distance) on the product of two sets.
(Contributed by Jim Kingdon, 11-Oct-2023.)
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| Theorem | xmetxpbl 15238* |
The maximum metric (Chebyshev distance) on the product of two sets,
expressed in terms of balls centered on a point with radius
.
(Contributed by Jim Kingdon, 22-Oct-2023.)
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                                                          |
| |
| Theorem | xmettxlem 15239* |
Lemma for xmettx 15240. (Contributed by Jim Kingdon, 15-Oct-2023.)
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| Theorem | xmettx 15240* |
The maximum metric (Chebyshev distance) on the product of two sets,
expressed as a binary topological product. (Contributed by Jim
Kingdon, 11-Oct-2023.)
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| 9.2.5 Continuity in metric spaces
|
| |
| Theorem | metcnp3 15241* |
Two ways to express that is continuous at for metric spaces.
Proposition 14-4.2 of [Gleason] p. 240.
(Contributed by NM,
17-May-2007.) (Revised by Mario Carneiro, 28-Aug-2015.)
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| Theorem | metcnp 15242* |
Two ways to say a mapping from metric to metric is
continuous at point . (Contributed by NM, 11-May-2007.) (Revised
by Mario Carneiro, 28-Aug-2015.)
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| Theorem | metcnp2 15243* |
Two ways to say a mapping from metric to metric is
continuous at point . The distance arguments are swapped compared
to metcnp 15242 (and Munkres' metcn 15244) for compatibility with df-lm 14920.
Definition 1.3-3 of [Kreyszig] p. 20.
(Contributed by NM, 4-Jun-2007.)
(Revised by Mario Carneiro, 13-Nov-2013.)
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| Theorem | metcn 15244* |
Two ways to say a mapping from metric to metric is
continuous. Theorem 10.1 of [Munkres]
p. 127. The second biconditional
argument says that for every positive "epsilon" there is a
positive "delta" such that a distance less than delta in
maps to a distance less than epsilon in . (Contributed by NM,
15-May-2007.) (Revised by Mario Carneiro, 28-Aug-2015.)
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| Theorem | metcnpi 15245* |
Epsilon-delta property of a continuous metric space function, with
function arguments as in metcnp 15242. (Contributed by NM, 17-Dec-2007.)
(Revised by Mario Carneiro, 13-Nov-2013.)
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| Theorem | metcnpi2 15246* |
Epsilon-delta property of a continuous metric space function, with
swapped distance function arguments as in metcnp2 15243. (Contributed by
NM, 16-Dec-2007.) (Revised by Mario Carneiro, 13-Nov-2013.)
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| Theorem | metcnpi3 15247* |
Epsilon-delta property of a metric space function continuous at .
A variation of metcnpi2 15246 with non-strict ordering. (Contributed by
NM,
16-Dec-2007.) (Revised by Mario Carneiro, 13-Nov-2013.)
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| Theorem | txmetcnp 15248* |
Continuity of a binary operation on metric spaces. (Contributed by
Mario Carneiro, 2-Sep-2015.) (Revised by Jim Kingdon, 22-Oct-2023.)
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| Theorem | txmetcn 15249* |
Continuity of a binary operation on metric spaces. (Contributed by
Mario Carneiro, 2-Sep-2015.)
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| Theorem | metcnpd 15250* |
Two ways to say a mapping from metric to metric is
continuous at point . (Contributed by Jim Kingdon,
14-Jun-2023.)
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| 9.2.6 Topology on the reals
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| Theorem | qtopbasss 15251* |
The set of open intervals with endpoints in a subset forms a basis for a
topology. (Contributed by Mario Carneiro, 17-Jun-2014.) (Revised by
Jim Kingdon, 22-May-2023.)
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              inf  
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| Theorem | qtopbas 15252 |
The set of open intervals with rational endpoints forms a basis for a
topology. (Contributed by NM, 8-Mar-2007.)
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| Theorem | retopbas 15253 |
A basis for the standard topology on the reals. (Contributed by NM,
6-Feb-2007.) (Proof shortened by Mario Carneiro, 17-Jun-2014.)
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| Theorem | retop 15254 |
The standard topology on the reals. (Contributed by FL, 4-Jun-2007.)
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| Theorem | uniretop 15255 |
The underlying set of the standard topology on the reals is the reals.
(Contributed by FL, 4-Jun-2007.)
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| Theorem | retopon 15256 |
The standard topology on the reals is a topology on the reals.
(Contributed by Mario Carneiro, 28-Aug-2015.)
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    TopOn   |
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| Theorem | retps 15257 |
The standard topological space on the reals. (Contributed by NM,
19-Oct-2012.)
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          TopSet  
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| Theorem | iooretopg 15258 |
Open intervals are open sets of the standard topology on the reals .
(Contributed by FL, 18-Jun-2007.) (Revised by Jim Kingdon,
23-May-2023.)
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| Theorem | cnmetdval 15259 |
Value of the distance function of the metric space of complex numbers.
(Contributed by NM, 9-Dec-2006.) (Revised by Mario Carneiro,
27-Dec-2014.)
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| Theorem | cnmet 15260 |
The absolute value metric determines a metric space on the complex
numbers. This theorem provides a link between complex numbers and
metrics spaces, making metric space theorems available for use with
complex numbers. (Contributed by FL, 9-Oct-2006.)
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| Theorem | cnxmet 15261 |
The absolute value metric is an extended metric. (Contributed by Mario
Carneiro, 28-Aug-2015.)
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      |
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| Theorem | cntoptopon 15262 |
The topology of the complex numbers is a topology. (Contributed by Jim
Kingdon, 6-Jun-2023.)
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     TopOn   |
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| Theorem | cntoptop 15263 |
The topology of the complex numbers is a topology. (Contributed by Jim
Kingdon, 6-Jun-2023.)
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      |
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| Theorem | cnbl0 15264 |
Two ways to write the open ball centered at zero. (Contributed by Mario
Carneiro, 8-Sep-2015.)
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| Theorem | cnblcld 15265* |
Two ways to write the closed ball centered at zero. (Contributed by
Mario Carneiro, 8-Sep-2015.)
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       ![[,] [,]](_icc.gif)           |
| |
| Theorem | cnfldms 15266 |
The complex number field is a metric space. (Contributed by Mario
Carneiro, 28-Aug-2015.)
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ℂfld  |
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| Theorem | cnfldxms 15267 |
The complex number field is a topological space. (Contributed by Mario
Carneiro, 28-Aug-2015.)
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ℂfld   |
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| Theorem | cnfldtps 15268 |
The complex number field is a topological space. (Contributed by Mario
Carneiro, 28-Aug-2015.)
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ℂfld  |
| |
| Theorem | cnfldtopn 15269 |
The topology of the complex numbers. (Contributed by Mario Carneiro,
28-Aug-2015.)
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  ℂfld       |
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| Theorem | cnfldtopon 15270 |
The topology of the complex numbers is a topology. (Contributed by
Mario Carneiro, 2-Sep-2015.)
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  ℂfld TopOn   |
| |
| Theorem | cnfldtop 15271 |
The topology of the complex numbers is a topology. (Contributed by
Mario Carneiro, 2-Sep-2015.)
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  ℂfld  |
| |
| Theorem | unicntopcntop 15272 |
The underlying set of the standard topology on the complex numbers is the
set of complex numbers. (Contributed by Glauco Siliprandi, 11-Dec-2019.)
(Revised by Jim Kingdon, 12-Dec-2023.)
|
       |
| |
| Theorem | unicntop 15273 |
The underlying set of the standard topology on the complex numbers is the
set of complex numbers. (Contributed by Glauco Siliprandi,
11-Dec-2019.)
|
   ℂfld |
| |
| Theorem | cnopncntop 15274 |
The set of complex numbers is open with respect to the standard topology
on complex numbers. (Contributed by Glauco Siliprandi, 11-Dec-2019.)
(Revised by Jim Kingdon, 12-Dec-2023.)
|
      |
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| Theorem | cnopn 15275 |
The set of complex numbers is open with respect to the standard topology
on complex numbers. (Contributed by Glauco Siliprandi, 11-Dec-2019.)
|
  ℂfld |
| |
| Theorem | reopnap 15276* |
The real numbers apart from a given real number form an open set.
(Contributed by Jim Kingdon, 13-Dec-2023.)
|
  #
       |
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| Theorem | remetdval 15277 |
Value of the distance function of the metric space of real numbers.
(Contributed by NM, 16-May-2007.)
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| Theorem | remet 15278 |
The absolute value metric determines a metric space on the reals.
(Contributed by NM, 10-Feb-2007.)
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          |
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| Theorem | rexmet 15279 |
The absolute value metric is an extended metric. (Contributed by Mario
Carneiro, 28-Aug-2015.)
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| Theorem | bl2ioo 15280 |
A ball in terms of an open interval of reals. (Contributed by NM,
18-May-2007.) (Revised by Mario Carneiro, 13-Nov-2013.)
|
                          |
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| Theorem | ioo2bl 15281 |
An open interval of reals in terms of a ball. (Contributed by NM,
18-May-2007.) (Revised by Mario Carneiro, 28-Aug-2015.)
|
                              |
| |
| Theorem | ioo2blex 15282 |
An open interval of reals in terms of a ball. (Contributed by Mario
Carneiro, 14-Nov-2013.)
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| Theorem | blssioo 15283 |
The balls of the standard real metric space are included in the open
real intervals. (Contributed by NM, 8-May-2007.) (Revised by Mario
Carneiro, 13-Nov-2013.)
|
        
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| Theorem | tgioo 15284 |
The topology generated by open intervals of reals is the same as the
open sets of the standard metric space on the reals. (Contributed by
NM, 7-May-2007.) (Revised by Mario Carneiro, 13-Nov-2013.)
|
              |
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| Theorem | tgqioo 15285 |
The topology generated by open intervals of reals with rational
endpoints is the same as the open sets of the standard metric space on
the reals. In particular, this proves that the standard topology on the
reals is second-countable. (Contributed by Mario Carneiro,
17-Jun-2014.)
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| Theorem | resubmet 15286 |
The subspace topology induced by a subset of the reals. (Contributed by
Jeff Madsen, 2-Sep-2009.) (Revised by Mario Carneiro, 13-Aug-2014.)
|
        
      ↾t    |
| |
| Theorem | tgioo2cntop 15287 |
The standard topology on the reals is a subspace of the complex metric
topology. (Contributed by Mario Carneiro, 13-Aug-2014.) (Revised by
Jim Kingdon, 6-Aug-2023.)
|
         
↾t   |
| |
| Theorem | rerestcntop 15288 |
The subspace topology induced by a subset of the reals. (Contributed by
Mario Carneiro, 13-Aug-2014.) (Revised by Jim Kingdon, 6-Aug-2023.)
|
          
↾t   ↾t    |
| |
| Theorem | tgioo2 15289 |
The standard topology on the reals is a subspace of the complex metric
topology. (Contributed by Mario Carneiro, 13-Aug-2014.)
|
  ℂfld   
 
↾t   |
| |
| Theorem | rerest 15290 |
The subspace topology induced by a subset of the reals. (Contributed by
Mario Carneiro, 13-Aug-2014.)
|
  ℂfld       ↾t 
 ↾t    |
| |
| Theorem | addcncntoplem 15291* |
Lemma for addcncntop 15292, subcncntop 15293, and mulcncntop 15294.
(Contributed by Mario Carneiro, 5-May-2014.) (Revised by Jim Kingdon,
22-Oct-2023.)
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| Theorem | addcncntop 15292 |
Complex number addition is a continuous function. Part of Proposition
14-4.16 of [Gleason] p. 243.
(Contributed by NM, 30-Jul-2007.) (Proof
shortened by Mario Carneiro, 5-May-2014.)
|
      
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| Theorem | subcncntop 15293 |
Complex number subtraction is a continuous function. Part of
Proposition 14-4.16 of [Gleason] p. 243.
(Contributed by NM,
4-Aug-2007.) (Proof shortened by Mario Carneiro, 5-May-2014.)
|
      
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| Theorem | mulcncntop 15294 |
Complex number multiplication is a continuous function. Part of
Proposition 14-4.16 of [Gleason] p. 243.
(Contributed by NM,
30-Jul-2007.) (Proof shortened by Mario Carneiro, 5-May-2014.)
|
    
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| Theorem | divcnap 15295* |
Complex number division is a continuous function, when the second
argument is apart from zero. (Contributed by Mario Carneiro,
12-Aug-2014.) (Revised by Jim Kingdon, 25-Oct-2023.)
|
      ↾t 
#    
 #       
  |
| |
| Theorem | mpomulcn 15296* |
Complex number multiplication is a continuous function. (Contributed by
GG, 16-Mar-2025.)
|
  ℂfld 
      
  |
| |
| Theorem | fsumcncntop 15297* |
A finite sum of functions to complex numbers from a common topological
space is continuous. The class expression for normally contains
free variables
and to index it.
(Contributed by NM,
8-Aug-2007.) (Revised by Mario Carneiro, 23-Aug-2014.)
|
      TopOn         
   
  
    |
| |
| Theorem | fsumcn 15298* |
A finite sum of functions to complex numbers from a common topological
space is continuous. The class expression for normally contains
free variables
and to index it.
(Contributed by NM,
8-Aug-2007.) (Revised by Mario Carneiro, 23-Aug-2014.)
|
  ℂfld  TopOn        
            |
| |
| Theorem | expcn 15299* |
The power function on complex numbers, for fixed exponent , is
continuous. (Contributed by Mario Carneiro, 5-May-2014.) (Revised by
Mario Carneiro, 23-Aug-2014.) Avoid ax-mulf 8155. (Revised by GG,
16-Mar-2025.)
|
  ℂfld 

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| 9.2.7 Topological definitions using the
reals
|
| |
| Syntax | ccncf 15300 |
Extend class notation to include the operation which returns a class of
continuous complex functions.
|
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